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                                                                   EXHIBIT 10.20

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, AND MAY NOT BE SOLD, ASSIGNED OR OTHERWISE TRANSFERRED IN THE ABSENCE
OF SUCH REGISTRATION OR AN EXEMPTION FROM SUCH REGISTRATION.


                                   PROMISSORY NOTE

                                                           February 3, 1998
                                                           Boston, Massachusetts

US$150,000

     FOR VALUE RECEIVED, the undersigned, Joseph Seebach (the "Maker"), hereby
promises to pay to the order of OneWave, Inc., a Delaware corporation (the
"PAYEE"), at such place or places as may be specified by the Payee, in lawful
money of the United States of America, the principal sum of ONE HUNDRED AND
FIFTY THOUSAND DOLLARS (US$150,000).  

     1.   PAYMENT OF PRINCIPAL AND INTEREST.  The principal sum of, and all
accrued but unpaid interest on, this Note shall be due and payable on December
31, 1999 or such earlier date as may be mutually agreed upon by the Maker and
the Payee, or as otherwise provided herein.  All amounts due and owing under
this Note shall bear interest at the rate of six and one-half percent (6 1/2%)
per annum on the unpaid balance, compounded quarterly.  The interest due shall
be paid within 30 days after the end of each calendar quarter.  All computations
of the interest rate hereunder shall be made on the basis of a three hundred and
sixty-five (365) day year and shall be paid for the actual number of days
elapsed on which the principal sum is outstanding.  This Note may be prepaid by
the Maker at any time without penalty.

     2.   SECURITY.  This Note is secured by a perfected, first priority
security interest in 100,000 shares of the common stock of OneWave, Inc. owned
by the Maker, in accordance with the terms of that certain Stock Pledge
Agreement by and between the Maker and the Payee dated February 3, 1998 (the
"Pledge Agreement").

     3.   EVENTS OF DEFAULT.  It shall be deemed an "Event of Default" hereunder
in the event of:  (i) an assignment for the benefit of creditors or commencement
of any proceeding under any bankruptcy or insolvency law by or against the
Maker, (ii) the termination, for any reason, of the Maker's employment with the
Payee or (iii) a material breach of the Pledge Agreement by the Maker.


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     4.   MAXIMUM RATE OF INTEREST.  All agreements between the Maker and the
Payee are hereby expressly limited so that in no contingency or event
whatsoever, whether by reason of acceleration of maturity of the indebtedness
evidenced hereby or otherwise, shall the amount paid or agreed to be paid to the
Payee for the use, forbearance or detention of the indebtedness evidenced hereby
exceed the maximum permissible under applicable law.  As used herein, the term
"applicable law" shall mean the law in effect as of the date hereof, PROVIDED,
HOWEVER, that in the event there is a change in the law which results in a
higher permissible rate of interest, then this Note shall be governed by such
new law as of its effective date.  If, from any circumstance whatsoever,
fulfillment of any provision hereof at the time performance of such provision
shall be due, shall involve transcending the limit of validity prescribed by
law, then the obligation to be fulfilled shall automatically be reduced to the
limit of such validity, and if from any circumstances the Payee should ever
receive as interest an amount which would exceed the highest lawful rate, such
amount in excess shall be applied first to the reduction of the principal
balance evidenced hereby.

     5.   WAIVERS OF CERTAIN RIGHTS.  The Maker hereby expressly waives
presentment, demand, protest and notice of every kind, and assents to the
substitution, release or addition of any collateral which at any time may be
security for payment of this Note.

     No delay or omission on the part of the Payee in exercising any rights
hereunder shall operate as a waiver of such rights or of any other right of the
Payee, nor shall any delay, omission or waiver on any one occasion be deemed a
bar to or waiver of the same or any other right on any future occasion.

     6.   EXPENSES.  The Maker will pay all costs and expenses of collection,
including reasonable attorney's fees, incurred or paid by the Payee in enforcing
this Note.

     7.   FURTHER ASSURANCES.  The Maker shall do, make, execute and deliver all
such additional and further acts, deeds, assurances and instruments as the Payee
may reasonably require to more completely vest in and assure to the Payee its
rights hereunder.

     8.   ASSIGNMENT; SUCCESSORS.  This Note is personal and may not be assigned
by the Maker.  This Note and all obligations of the Maker hereunder shall be
binding upon his heirs, executors and administrators.  The Payee shall have the
right to assign this Note, without any restriction.  The Payee's rights and
remedies under this Note shall inure to the benefit of its assigns and
successors by way of merger, consolidation or sale of substantially all of the
assets or stock of the Payee.  

     9.   GOVERNING LAW.  This Note shall be governed by and construed under the
laws of The Commonwealth of Massachusetts, without giving effect to the conflict
of laws principles thereof.  If any provision of this Note is held to be invalid
or unenforceable by a court of competent jurisdiction, the other provisions of
this Note shall remain in full force and effect.


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WITNESS:                      MAKER:

                              JOSEPH SEEBACH



/s/ David W. Chapman          /s/ Joseph Seebach
---------------------------   ------------------------------------




                              PAYEE:

                              ONEWAVE, INC.



                              By: /s/ Lennart Mengwall
                                  -------------------------
                                  Name: Lennart Mengwall
                                  Title:   President & CEO




DOCSC\592803.1