EXHIBIT 4.15

                      Registered Holder: MCI WORLDCOM, Inc.


                                  $25,000,000


                                  WAM!NET, Inc.
                             6100 WEST 110th STREET
                          MINNEAPOLIS, MINNESOTA 55438


                 13.25% Subordinated Unsecured Convertible Note
                               Due August 28, 2005


         For Value Received, WAM!NET, Inc., a Minnesota corporation (hereinafter
called the "Issuer"), hereby promises to pay to the order of MCI WORLDCOM, Inc.,
or the registered holder (hereinafter referred to as the "Holder") the principal
amount of Twenty Five Million Dollars ($25,000,000) or such lesser amount as has
been actually advanced to the Issuer by the Holder pursuant to that certain
Subordinated Unsecured Convertible Note and Warrant Purchase Agreement of even
date herewith, upon presentation of this certificate, in legal tender of the
United States of America at the time of payment hereof, to the account of holder
according to Holder's written instructions, on August 28, 2005, being one
hundred eighty (180) days after the maturity of the Senior Notes, as hereinafter
defined. The indebtedness evidenced by this Subordinated Unsecured Convertible
Note (this or the "Note") constitutes "Deeply Subordinated Indebtedness" for
purposes of the Indenture (the "Indenture") relating to the Senior Notes as
defined below.

         The Issuer further agrees to pay interest on the principal amount
remaining unpaid from time to time thereon from the date hereof at the rate of
thirteen and one-quarter percent (13.25%) per annum. Interest shall accrue on a
monthly basis from the date of purchase of the Note, and be payable upon the due
date of this Note. The Issuer shall, upon the due date and with or without
demand or other request by the registered Holder, mail a check or draft
representing such interest and the unpaid principal balance to the registered
holder at the address designated by the registered holder and appearing on the
books of registration maintained by the Issuer.

         The following terms, covenants, statements of Holders' rights and
conditions shall apply to this Note.

                                   ARTICLE 1.

                                  SUBORDINATION

                   1.1. The Issuer and the Holder of this Note, by acceptance
hereof, agree that the payment of the principal and interest on this Note is, to
the extent stated herein expressly subordinated to the prior payment in full of
all existing

 
obligations of the Issuer for money borrowed from a bank, trust,
insurance, or other financial institution engaged in the business of lending
money, and with respect to the Issuer's Senior Discount Notes due 2005 issued
March 5, 1998 ("Senior Notes"), which collectively are hereinafter referred to
as "Senior Indebtedness." In no event shall the Issuer make any payments in
respect of this Note prior to the date that is 180 days following the stated
maturity of the principal of any Senior Indebtedness, except: (a) that this Note
may be redeemed or retired by the Issuer or converted in accordance with the
terms hereof into capital stock of the Issuer; and (b) the payment principal of
and interest on this Note may be accelerated in accordance with the terms hereof
only in the event of the acceleration of the payment of the principal amount of
the Senior Notes following an event of default in respect of such Senior Notes,
provided that any payment in respect of this Note following the acceleration
thereof shall be subordinated to the prior payment in full of all amounts due in
respect of the Senior Notes and under the Indenture, and provided further, that
in the event of the recession of any such acceleration of the Senior Notes, the
acceleration of this Note shall be deemed rescinded upon notice to such effect
to the Holder from the Indenture trustee with respect to the Senior Notes.

                                   ARTICLE 2.

                                EVENT OF DEFAULT

                   2.1. Each of the following shall constitute an Event of
Default:

                  (a)      Failure to pay principal and interest when due;

                  (b) An assignment for the benefit of creditors of the Issuer,
adjudication of Issuer as a bankrupt, or petition for the reorganization of the
Issuer pursuant to Chapter X or XI of the United States Bankruptcy Act, as the
same may be amended.

                   2.2. Upon the occurrence of any Event of Default specified in
(b) above, the entire unpaid principal balance hereof, together with all accrued
and unpaid interest thereon and all other sums owing hereunder, shall become
immediately due and payable, without presentation, demand or further action of
any kind. Upon the occurrence of any Event of Default specified in (a) above,
the holder of this Note shall have the sole option of declaring the unpaid
principal balance hereof together with all other sums owing hereunder
immediately due and payable, without presentation, demand or further action of
any kind.

                   2.3. Upon the occurrence of any Event of Default and before
and after acceleration of the entire unpaid principal balance of this Note,
interest shall continue to accrue thereafter on the unpaid principal amount of
this Note at a rate equal to two percent (2%) per annum in excess of the then

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applicable rate of interest under this Note until this Note is paid in full,
including the period following entry of any judgment. Both before and after any
default, interest shall be calculated on the basis of a 360-day year but charged
on the basis of actual number of days elapsed in any calendar year or part
thereof.

                   2.4. Holder may waive any default before or after the same
has been declared without impairing the Holder's right to declare a subsequent
default hereunder, this right being a continuing right.

                   2.5. Upon an Event of Default, Holder shall not be deemed, by
any act of omission or commission to have waived any of its rights or remedies
unless such waiver is in writing and signed by Holder, and then only to the
extent specifically set forth in the writing. A waiver as to one event shall not
be construed as continuing or as a bar to or waiver of any right or remedy as to
a subsequent event.

                                   ARTICLE 3.

                              PREPAYMENT BY ISSUER

                   3.1.  This Note may be prepaid at any time after
April 30, 1999, in whole or in part, prior to maturity at the option of the
Issuer, on at least twenty (20) days' written notice by registered mail by the
Issuer to the Holder, upon payment of all, or such lesser portion of the
principal amount as specified in the notice, together with interest accrued to
the date fixed for prepayment. If the Holder hereof fails or neglects to present
this Note for payment at the time and place specified in such notice, this Note
shall continue to bear interest regardless of whether or not payment hereof is
refused upon the presentation of the same at or after the time specified in such
notice.

                                   ARTICLE 4.

                       CONVERSION OF NOTE TO COMMON STOCK
                             AT THE OPTION OF HOLDER

                   4.1. The Holder of this Note shall have the right, at its
option in accordance with the terms of this Article 4, to convert the then
outstanding principal amount of this Note, or any portion thereof, and any
accrued interest thereon, into shares of the Capital Stock of the Issuer
("Stock") at a price per share determined as hereinafter described (such price
hereinafter referred to as the "Conversion Price") upon surrender of this Note
at the principal office of the Issuer, together with written notice (hereinafter
referred to as the "Conversion Notice"), in form appended hereto, of the
election executed by the Holder and specifying the name or names in which the
shares of Stock deliverable upon such conversion shall be registered,

                                      -3-

 
along with the addresses of the persons so named and, if required by the Issuer,
accompanied by a written instrument of transfer in form satisfactory to the
Issuer duly executed by the Holder; provided, however, that if this Note has
been called for prepayment according to the terms of Article 3 prior to the
receipt by Issuer of the Conversion Notice, the right of the Holder to convert
this Note shall terminate on the date fixed for prepayment.

                   4.2. If the Equity Offering as defined in Section 4A.1 is not
consummated by April 30, 1999, the Holder shall have the right, at its option,
to convert at any time after April 30, 1999 and prior to the due date of this
Note, the then outstanding principal amount of this Note, or any portions
thereof plus accrued interest thereon into Common Stock of the Issuer, par value
$.01 ("Common Stock"), at a Conversion Price equal to the per share fair market
value of the Common Stock as of the date of the receipt by Issuer of the
Conversion Notice from Holder with respect to its election to convert as
determined in accordance with Section 4.3.

                   4.3. In the event the Holder elects to convert part or all of
the outstanding principal and accrued interest thereon of this Note to Common
Stock under Section 4.2 above, the Issuer (acting through its directors who are
not affiliated with the Holder) and the Holder shall, within twenty (20) days of
the receipt of the Conversion Notice, utilize their reasonable efforts to reach
an agreement as to the per share fair market value of the Common Stock. In the
event the parties are unable to do so, WAM!NET's management and Board of
Directors shall promptly obtain from a nationally recognized investment banking
firm a valuation of the fair market value per share of WAM!NET's Common Stock.
In such case, the fees and expenses of the investment banking firm shall be
borne one-half by the Issuer and one-half by the Holder.

                  4.4. Stock issued on conversion of this Note pursuant to
Section 4.1 shall be delivered as follows:

                  (a) Within fifteen (15) days after the surrender of this Note
for conversion and the receipt of the Conversion Notice, the Issuer shall
deliver to the Holder, or to such person or persons so designated by the Holder
in the Conversion Notice, a certificate or certificates representing the number
of fully paid and non-assessable shares of Stock into which this Note or portion
thereof is to be converted in such name or names as are specified in the
Conversion Notice, together with any cash payable in lieu of any fractional
share as provided in Section 4.6. Such conversion shall be deemed to have been
effected at the close of business on the date when this Note shall have been
surrendered for conversion together with the Conversion Notice, so that the
person entitled to receive the shares of Stock upon conversion shall be treated
for all purposes as having become the record holder of such shares of Stock at
such time and the

                                      -4-

 
conversion shall be at the Conversion Price in effect at the
time.

                  (b) In the event less than the entire outstanding principal
balance of this Note shall be converted hereunder, this Note shall not be
surrendered for cancellation but shall have the fact and amount of conversion
recorded on the face of this Note by writing acknowledged by the Holder and the
Issuer.

                  4.5. In the case of any consolidation or merger of the Issuer
with another corporation, or the sale of all or substantially all of its assets
to another person, or any reorganization or reclassification of the capital
stock of the Issuer:

                  (a) as a condition of such consolidation, merger, sale,
reorganization or reclassification, lawful and adequate provision shall be made
whereby the Holder shall thereafter have the right to receive upon the basis and
upon the terms and conditions specified herein and in lieu of the shares of the
Stock immediately theretofore subject to acquisition hereunder, such securities
or assets as may (by virtue of such consolidation, merger, sale, reorganization
or reclassification) be issued or payable with respect to or in exchange for a
number of outstanding shares of such Stock equal to the number of shares of such
Common Stock immediately theretofore so subject to acquisition hereunder had
such consolidation, merger, sale, reorganization or reclassification not taken
place, and in any such case appropriate provisions shall be made with respect to
the rights and interests of the Holder to the end that the provisions hereof
shall thereafter be applicable as nearly as may be, in relation to any
securities or assets thereafter deliverable upon the exercise of the conversion
option. The Issuer shall not effect any such consolidation, merger or sale,
unless prior to or simultaneously with the consummation thereof, the successor
person or persons purchasing such assets or succeeding or resulting from such
consolidation, merger, reorganization or reclassification shall assume by
written instrument executed and mailed or delivered to the Holder, the
obligation to deliver to such Holder such securities or assets as, in accordance
with the foregoing provisions, the Holder may be entitled to receive.

                  (b) In the event that the Issuer shall make any distribution
of its assets upon or with respect to its Common Stock, as a liquidating or
partial liquidation dividend, or other than as a dividend payable out of
earnings or any surplus legally available for dividends under the laws of the
State of Minnesota, the Holder shall, upon conversion of the Note in accordance
with the terms of the Note after the record date for such distribution or, in
the absence of a record date, after the date of such distribution, receive in
addition to the shares subscribed for, the amount of such assets (or, at the
option of the Issuer, a sum equal to the value thereof at the time of
distribution as

                                      -5-

 
determined in good faith by the Board of Directors in its sole discretion) which
would have been distributed to the Holder if this Note had been converted
immediately prior to the record date for such distribution or, in the absence of
a record date, immediately prior to the date of such distribution.

                  4.6. Fractional shares shall not be issued upon conversion of
this Note but in any case where the Holder would, except for the provisions of
this Article, be entitled under the terms hereof to receive a fractional share,
the Issuer shall, upon any conversion for the largest number of whole shares
then called for, pay a sum in cash equal to the sum of the proportional part of
the per share Conversion Price represented by such fractional share.

                                   ARTICLE 4A.

                              AUTOMATIC CONVERSION

                  4A.1. If on or before April 30, 1999, the Issuer consummates
an equity offering resulting in gross proceeds in cash and non-cash
consideration as provided in the Loan Agreement having an aggregate value of a
minimum of Seventy-Five Million Dollars ($75,000,000.00) (an "Equity Offering"),
the then outstanding principal amount of this Note and any accrued interest
thereon shall, upon such consummation automatically and without any action on
the part of the Holder or Issuer convert into the same class of shares sold in
the Equity Offering and at a Conversion Price equal to the offering price per
share in the Equity Offering.

                                   ARTICLE 5.

                               REGISTRATION RIGHT

                  5.1. (a) If, commencing one (1) year after the date hereof,
the Issuer proposes to claim an exemption under Section 3(b) for a public
offering of any of its securities or to register under the Securities Act of
1933 (except by a claim of exemption or registration statement on a form that
does not permit the inclusion of shares by its security holders) any of its
securities, it will give written notice to the registered Holder of this Note,
and all registered Holders of shares of common stock acquired upon the
conversion of this Note, of its intention to do so and, on the written request
of any such registered holders given within twenty (20) days after receipt of
any such notice (which request must be made within five (5) years from the date
of this Note and which notice shall specify the shares of common stock intended
to be sold or disposed of by such registered holder and describe the nature of
any proposed sale or other disposition thereof), the Issuer will use its best
efforts to cause all such shares, the registered holders of which shall have
requested the registration or qualification thereof, to be included in such
notification of registration statement proposed

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to be filed by the Issuer; provided, however, that nothing herein shall prevent
the Issuer from, at any time, abandoning or delaying any such registration
initiated by it. If any such registration shall be underwritten in whole or in
part, the Issuer may require that the shares requested for inclusion pursuant to
this section be included in the underwriting on the same terms and conditions as
the securities otherwise being sold through the underwriters. If in the good
faith judgment, as expressed in writing delivered to the registered holder(s),
of the managing underwriter of such public offering the inclusion of all of the
shares originally covered by a request for registration would reduce the number
of shares to be offered by the Issuer or interfere with the successful marketing
of the shares of stock offered by the Issuer, the number of shares otherwise to
be included pursuant to this Section in the underwritten public offering may be
reduced; provided, however, that any such required reduction shall be pro rata
among all persons (other than the Issuer) who are participating in such
offering. Those shares which are thus excluded from the underwritten public
offering shall be withheld from the market for a period, not to exceed 90 days,
which the managing underwriter reasonably determines is necessary in order to
effect the underwritten public offering. All expenses of such offering, except
the fees of special counsel to such holders and brokers' commissions or
underwriting discounts payable by such holders, shall be borne by the Issuer.

                  (b) Further, on one occasion only, commencing one (1) year
after the date hereof, upon request by the holder of the Note and/or the holders
of shares issued upon the conversion of the Note who collectively have the right
to purchase at least 500,000 shares or hold directly at least 500,000 shares
purchased hereunder or have the right to purchase and hold directly an aggregate
of at least 500,000 shares purchasable or purchased hereunder, the Issuer will
promptly use its reasonable best efforts to register or qualify the Note or such
shares under Section 3(b) or Section 5 of the Securities Act of 1933 (and, upon
the request of such holders, under Rule 415 thereunder) and such state laws as
such holders may reasonably request; provided that (i) such request must be made
within five (5) years from the date of this Note; and (ii) the Issuer may delay
the filing of any registration statement requested pursuant to this section to a
date not more than ninety (90) days following the date of such request if in the
opinion of the Issuer's principal investment banker at the time of such request
such a delay is necessary in order not to adversely affect financing efforts
then underway at the Issuer, or if in the opinion of the Issuer such a delay is
necessary or advisable to avoid disclosure of material nonpublic information.
The costs and expenses directly related to any registration requested pursuant
to this section, including but not limited to legal fees of the Issuer's
counsel, audit fees, printing expense, filing fees and fees and expenses
relating to qualifications under state securities or blue sky laws incurred by
the Issuer shall be borne entirely by the Issuer; provided,

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however, that the persons for whose account the securities covered by such
registration are sold shall bear the expenses of underwriting commissions
applicable to their shares and fees of their legal counsel. If the holder of the
Note and the holders of shares of Common Stock underlying the Note are the only
persons whose shares are included in the registration pursuant to this section,
such holders shall bear the expense of inclusion of audited financial statements
in the registration statement which are not dated as of the Issuer's normal
fiscal year or are not otherwise prepared by the Issuer for its own business
purposes. The Issuer shall keep effective and maintain any registration,
qualification, notification or approval specified in this paragraph for such
period as may be necessary for the holders of the Note and such common stock to
dispose thereof, and from time to time shall amend or supplement, at the
holder's expense, the prospectus or offering circular used in connection
therewith to the extent necessary in order to comply with applicable law;
provided, that the Issuer shall not be obligated to maintain any registration
for a period of more than nine (9) months.

                  If, at the time any written request for registration is
received by the Issuer pursuant to this Section 5.1(b) the Issuer has determined
to proceed with the actual preparation and filing of a registration statement
under the Securities Act in connection with the proposed offer and sale for cash
of any of its securities by it or any of its security holders, such written
request shall be deemed to have been given pursuant to Section 5.1(a) rather
than to this Section 5.1(b), and the rights of the holders of the Note and/or
shares issued upon the conversion of the Note covered by such written request
shall be governed by Section 5.1(a) hereof.

                  (c) If and whenever the Issuer is required by the provisions
of Sections 5.1(a) or 5.1(b) hereof to effect the registration of shares issued
upon the exercise of the Note under the Securities Act, the Issuer will:

                           (i) Prepare and file with the Commission a
         registration statement with respect to such securities, and use its
         best efforts to cause such registration statement to become and remain
         effective for such period as may be reasonably necessary to effect the
         sale of such securities, not to exceed nine (9) months;

                           (ii) prepare and file with the Commission such
         amendments to such registration statement and supplements to the
         prospectus contained therein as may be necessary to keep such
         registration statement effective for such period as may be reasonably
         necessary to effect the sale of such securities, not to exceed nine (9)
         months;

                           (iii) furnish to the security holders participating
         in such registration and to the underwriters of the securities being
         registered such reasonable number of

                                      -8-

 
         copies of the registration statement, preliminary prospectus, final
         prospectus and such other documents as such underwriters may reasonably
         request in order to facilitate the public offering of such securities;

                           (iv) use its best efforts to register or qualify the
         securities covered by such registration statement under such state
         securities or blue sky laws of such jurisdictions as such participating
         holders may reasonably request in writing within 30 days following the
         original filing of such registration statement, except that the Issuer
         shall not for any purpose be required to execute a general consent to
         service of process or to qualify to do business as a foreign
         corporation in any jurisdiction wherein it is not so qualified;

                           (v) notify the security holders participating in such
         registration, promptly after it shall receive notice thereof, of the
         time when such registration statement has become effective or a
         supplement to any prospectus forming a part of such registration
         statement has been filed;

                           (vi) notify such holders promptly of any request by
         the Commission for the amending or supplementing of such registration
         statement or prospectus or for additional information;

                           (vii) prepare and file with the Commission, promptly
         upon the request of any such holders, any amendments or supplements to
         such registration statement or prospectus which, in the opinion of
         counsel for such holders (and concurred in by counsel for the Issuer),
         is required under the Securities Act or the rules and regulations
         thereunder in connection with the distribution of the Note or shares by
         such holder;

                           (viii) prepare and promptly file with the Commission
         and promptly notify such holders of the filing of such amendment or
         supplement to such registration statement or prospectus as may be
         necessary to correct any statements or omissions if at the time when a
         prospectus relating to such securities is required to be delivered
         under the Securities Act, any event shall have occurred as the result
         of which any such prospectus or any other prospectus as then in effect
         would include an untrue statement of a material fact or omit to state
         any material fact necessary to make the statements therein, in the
         light of the circumstances in which they were made, not misleading;

                           (ix) advise such holders, promptly after it shall
         receive notice or obtain knowledge thereof, of the issuance of any stop
         order by the Commission suspending the effectiveness of such
         registration statement or the initiation or threatening of any
         proceeding for that purpose

                                      -9-

 
         and promptly use its best efforts to prevent the issuance of any stop
         order or to obtain its withdrawal if such stop order should be issued;

                           (x) not file any amendment or supplement to such
         registration statement or prospectus to which a majority in interest of
         such holders shall have reasonably objected on the grounds that such
         amendment or supplement does not comply in all material respects with
         the requirements of the Securities Act or the rules and regulations
         thereunder, after having been furnished with a copy thereof at least
         five business days prior to the filing thereof, unless in the opinion
         of counsel for the Issuer the filing of such amendment or supplement is
         reasonably necessary to protect the Issuer from any liabilities under
         any applicable federal or state law and such filing will not violate
         applicable law; and

                           (xi) at the request of any such holder, furnish on
         the effective date of the registration statement and, if such
         registration includes an underwritten public offering, at the closing
         provided for in the underwriting agreement: (i) opinions, dated such
         respective dates, of the counsel representing the Issuer for the
         purposes of such registration, addressed to the underwriters, if any,
         and to the holder or holders making such request, covering such matters
         as such underwriters and holder or holders may reasonably request; and
         (ii) letters, dated such respective dates, from the independent
         certified public accountants of the Issuer, addressed to the
         underwriters, if any, and to the holder or holders making such request,
         covering such matters as such underwriters and holder or holders may
         reasonably request, in which letter such accountants shall state
         (without limiting the generality of the foregoing) that they are
         independent certified public accountants within the meaning of the
         Securities Act and that in the opinion of such accountants the
         financial statements and other financial data of the Issuer included in
         the registration statement or the prospectus or any amendment or
         supplement thereto comply in all material respects with the applicable
         accounting requirements of the Securities Act.

                  (d) The Issuer hereby indemnifies the holder of this Note and
of any common or other stock issued or issuable hereunder, its officers,
directors, employees and agents, and any person who controls such Note holder or
such holder of common or other stock within the meaning of Section 15 of the
Securities Act of 1933, against all losses, claims, damages and liabilities
caused by any untrue statement of a material fact contained in any registration
statement, prospectus, notification or offering circular (and as amended or
supplemented if the Issuer shall have furnished any amendments or supplements
thereto) or any preliminary prospectus or caused by any omission to state
therein a material fact required to be stated therein or necessary to

                                      -10-

 
make the statements therein not misleading except insofar as such losses,
claims, damages or liabilities are caused by any untrue statement or omission
contained in information furnished in writing to the Issuer by such Note holder
or such holder of common or other stock expressly for use therein, and each such
holder by its acceptance hereof severally agrees that it will indemnify and hold
harmless the Issuer and each of its officers who signs such registration
statement and each of its directors and each person, if any, who controls the
Issuer within the meaning of Section 15 of the Securities Act of 1933 with
respect to losses, claims, damages or liabilities which are caused by any untrue
statement or omission contained in information furnished in writing to the
Issuer by such holder expressly for use therein.

                  (e) If the indemnification provided for in Article 5 is
unavailable to an indemnified party as provided herein in respect of any losses,
claims, damages, liabilities or expenses referred to therein, then the Issuer,
in lieu of indemnifying such indemnified party, shall contribute to the amount
paid or payable by such indemnified party as a result of such losses, claims,
damages, liabilities or expenses in such proportion as is appropriate to reflect
the relative fault of the Issuer on the one hand and the holder of this Note on
the other in connection with the statements or omissions which resulted in such
losses, claims, damages, liabilities or expenses, as well as any other relevant
equitable considerations. The relative fault of the Issuer on the one hand and
of the holder of this Note on the other shall be determined by reference to,
among other things, whether the untrue or alleged untrue statements of a
material fact of the omission or alleged omission to state a material fact
relates to information supplied by the Issuer or by the holder of this Note is
and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent, such statement or omission. The amount paid
or payable by a party as a result of the losses, claims, damages, liabilities
and expenses referred to above shall be deemed to include, without limitation,
any legal or other fees or expenses reasonably incurred by such party in
connection with investigating or defending any action or claim.

                  The Issuer and the holder of this Note agree that it would not
be just and equitable if contribution pursuant to this Section 5.1(e) were
determined by a pro rata allocation or by any other method of allocation that
does not take account of the equitable considerations referred to in the
immediately preceding paragraph. Notwithstanding the provisions of this Section
5.1(c), the holder of this Note shall not be required to contribute any amount
in excess of the amount by which the total price which such holder's
registerable securities were sold to the public. No person guilty of fraudulent
misrepresentations (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation.

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                                   ARTICLE 6.

                                    REGISTRY

                   6.1. Books for the registry hereof are kept at the office of
the Issuer. No transfer hereof shall be valid unless made on the Issuer's books
at the office of the Issuer, by the Holder, in person, or by an attorney duly
authorized in writing, similarly noted hereon.

                                   ARTICLE 7.

                                     PAYMENT

                   7.1. Payment to the Holder of principal and interest shall be
a complete discharge of the Issuer's liability with respect to such payment, but
the Issuer may, at any time, require the presentation hereof as a condition
precedent to such payment.

                   7.2. No recourse shall be had for the payment of the
principal, or interest, or for any claim based thereof, or otherwise, against
any incorporator, shareholder, officer, director, or agent, past, present, or
future, of the Issuer, whether by virtue of any constitution, statute, rule of
law, enforcement of any assessment, or penalty, or by reason of any matter prior
to delivery of this Note, or otherwise. All such liability, by the acceptance
hereof, is a part of the consideration to the Issuer hereof, and is expressly
waived.

                                   ARTICLE 8.

                                    DIVIDENDS

                   8.1. Until payment in full or conversion of this Note, the
Issuer may not declare any dividend payable in cash or property on its Common
Stock, with the sole exception of any stock split in the form of a dividend
payable in shares of common stock to which the provisions of Article IV hereof
apply.

                                   ARTICLE 9.

                                    OWNERSHIP

                   9.1. The Issuer may treat the person(s) in whose name this
Note is issued as the absolute owner(s) hereof for all purposes, whether or not
this Note is overdue and the Issuer shall not be affected by any notice to the
contrary.

                                   ARTICLE 10.

                                     NOTICE

                   10.1. All notices, requests, demands and other communications
under this Note shall be in writing and shall be

                                      -12-

 
deemed to have been given on the date of service if served personally on the
party to whom notice is to be given, or on the third day after mailing if mailed
to the party to whom notice is to be given by first class mail, registered or
certified, postage prepaid to the Issuer at its address stated on the front page
of this Note and to the Holder at its address as listed in the register of the
Issuer. Either party may change its address for purposes of this Article 10.1 by
giving the other party written notice of the new address in the manner set forth
above.

                                   ARTICLE 11.

                                  MISCELLANEOUS

                   11.1. All parties liable for the payment of this Note agree
to pay on demand, all costs of collection and to cure any default under this
Note including, but not limited to, reasonable attorneys' fees actually
incurred.

                   11.2. The undersigned and all endorsers, sureties and
guarantors of this Note jointly and severally waive notice of and consent to any
and all extensions of this Note or any part hereof without notice, and each
hereby waives presentment, demand for payment, protest and notice of dishonor,
demand, protest and nonpayment.

                   11.3. The remedies of Holder as provided herein shall be
cumulative and concurrent, and may be pursued singularly, successively or
together against Issuer at the sole discretion of Holder, and the failure to
exercise any such right or remedy shall in no event be construed as a waiver or
release of the same.

                   11.4. Issuer's obligations hereunder shall extend to and bind
Issuer's successors and assigns. This Note may be amended only by an instrument
in writing signed by both Issuer and Holder.

                  IN WITNESS WHEREOF, the Issuer has caused this Note to be
signed by its Chief Financial Officer.

Dated:  January ____, 1999          WAM!NET, Inc.
                                    
                                    
                                    By:   /s/Brad Sparks
                                          -------------------------
                                          Brad Sparks
                                    Its:  Chief Financial Officer

                                      -13-

 
                               CONVERSION NOTICE

                               To WAM!NET, Inc.

                  The undersigned holder of this Note hereby irrevocably
exercises the option to convert this Note as indicated below:

                  __________ The undersigned elects to convert $_________ in
principal of this Note and accrued interest thereon into Common Stock of
WAM!NET, Inc. in accordance with the terms of Section 4 of this Note.

                  The undersigned holder of this Note directs that the shares
issuable and deliverable upon the conversion be issued and delivered to the
undersigned unless a different name has been indicated below. Additionally, as a
condition to such conversion privilege, the undersigned holder of this Note
agrees to execute a letter stating its investment intent is to hold the shares
issuable upon conversion for investment and not for resale, except in accordance
with the requirements is of Rule 144 of the General Rules and Regulations under
the Securities Act of 1933, or any successor Rule together with applicable state
securities law, and agrees that the certificates representing the shares
issuable and deliverable upon conversion may be imprinted with a legend in
customary form reciting the restrictions on transfer mandated by such laws.

Dated:___________                    NOTE HOLDER:
                                     
                                     -------------------------------
                                     Name (Please Print)
                                     
                                     -------------------------------
                                     Address

                                     -------------------------------
                                     City, State and Zip

                                     -------------------------------
                                     Signature

If shares are to be issued otherwise than to owner please provide name and
address of person or persons to whom shares are to be issued:

                                     -------------------------------
                                     Name (Please Print)

                                     -------------------------------
                                     Address

                                     -------------------------------
                                     City, State and Zip

                                      -14-