THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "ACT"), UNDER ANY STATE SECURITIES LAW, OR UNDER ANY "BLUE SKY"
LAWS, AND THIS SECURITY MAY NOT BE OFFERED, SOLD, ASSIGNED, TRANSFERRED,
PLEDGED, OR OTHERWISE DISPOSED OF, UNLESS REGISTERED PURSUANT TO THE PROVISIONS
OF THE ACT AND OF THE "BLUE SKY" LAWS, OR UNLESS AN EXEMPTION THEREFROM IS
AVAILABLE, AS ESTABLISHED BY A WRITTEN OPINION OF COUNSEL ACCEPTABLE TO THE
MAKER.


                                  CMGI, INC.


                                PROMISSORY NOTE
                                ---------------

August 18, 1999
Andover, Massachusetts                                      $138,000,000.00

     FOR VALUE RECEIVED, CMGI, Inc., a Delaware corporation ("Maker"), promises
to pay to the order of Digital Equipment Corporation, a Massachusetts
corporation ("Holder"), at the offices or the Holder, or at such other place as
the Holder may designate, the principal sum of one hundred thirty eight million
dollars ($138,000,000.00), together with interest on the unpaid principal
balance of this Note from time to time outstanding, at the rate of 10.5% per
annum (except as set forth in Section 3 below), until the principal hereof is
paid in full.  The following is a statement of the rights of the Holder and the
conditions to which this Note is subject, to which Holder, by acceptance of this
Note, agrees:

     1.   MATURITY.  The principal amount of the Note shall be due and payable
on August 18, 2002 (the "Maturity Date").

     2.   MEANS OF PAYMENT.  Any principal and any interest may be paid, in the
sole discretion of the Maker, in (i) cash, (ii) Marketable Securities (as
defined below), or (iii) any combination of the foregoing.

     3.   INTEREST RATE.  Interest shall be computed at the annual rate of 10.5%
on the outstanding principal balance of this Note and shall be calculated on the
basis of a 360-day year.  If the Maker fails to present to the Holder any
interest payment when due, and if such failure to pay is not cured by the Maker
within ten (10) Business Days after the due date, then the interest rate will
increase to 13.5% per annum until such default is cured.

                                       1
<PAGE>

     4.   INTEREST PAYMENT DATES.  Interest shall be payable semiannually in
arrears on each February 18 and August 18 until the principal amount hereby is
paid in full.

     5.   NON-CASH PAYMENTS.

          (a) "Marketable Securities" shall mean any shares of common stock of
the Maker or any other company that (i) are traded on the New York Stock
Exchange, American Stock Exchange or Nasdaq National Market, and (ii) upon
issuance or delivery to the Holder in payment of this Note, shall be (a) freely
eligible for resale by the Holder pursuant to Rule 144(k) under the Securities
Act of 1933 (the "Securities Act") or otherwise, or (b) eligible for resale
pursuant to Rule 144 under the Act and able to be sold in full within the three-
month period following the date of delivery to the Holder.

          (b) The value of any Marketable Securities shall be determined using
the average closing prices for such Marketable Securities during the period
beginning on the applicable Notification Date (as defined below) and ending on
the trading day immediately preceding the applicable date of the payment made by
delivery of such Marketable Securities (the "Payment Date").  If the Maker
intends to make a payment by delivery of Marketable Securities, the Maker shall
provide written notice of the issuer or issuers of such Marketable Securities
and the approximate amount of the payment to be made by delivery of Marketable
Securities of any such issuer to the Holder on or prior to the date fifteen (15)
business days prior to the applicable Payment Date (the "Notification Date").

     6.   PREPAYMENT.  This Note may be prepaid in whole or in part at any time,
with or without prior written notice to the Holder, at the sole discretion of
the Maker.  Any such prepayment shall be without premium or penalty.

     7.   EVENTS OF DEFAULT.  At the sole discretion of the Holder, all
outstanding principal and interest shall immediately become payable in full upon
the occurrence at any time of any of the following events of default
(individually, an "Event of Default" and collectively, "Events of Default"):

          (a)  the failure of the Maker to present to the Holder, in full
               amount, any interest payment due, if and only if such failure to
               pay is not cured by the Maker within ten (10) Business Days of
               the due date, provided the Holder gives three (3) Business Days
               prior written notice to the Maker of such failure and the Maker
               has an opportunity to cure such failure;

                                       2
<PAGE>

          (b)  the liquidation, termination of existence, dissolution,
               insolvency, or business failure of the Maker, or the appointment
               of a receiver or custodian for the Maker or for any part of its
               property, if such appointment is not terminated or dismissed
               within sixty (60) days; or

          (c)  the institution against the Maker of any proceedings under the
               United States Bankruptcy Code or under any other federal or state
               bankruptcy, reorganization, receivership, insolvency, or other
               similar law affecting the rights of creditors generally, which
               proceeding is not dismissed within sixty (60) days of filing.

     8.   RIGHTS OF HOLDER UPON DEFAULT.  Upon the occurrence of an Event of
Default, the Holder shall have then, and shall have at any time thereafter, all
of the rights and remedies afforded by the Uniform Commercial Code as from time
to time in effect in the Commonwealth of Massachusetts or afforded by other
applicable law.

     9.   USURY.  In no event shall any interest charged, collected, or reserved
under this Note exceed the maximum rate then permitted by applicable law, and,
if any such payment is paid by the Maker, then such excess sum shall be credited
by the Holder as a payment of principal.

     10.  RANKING.  This Note will not be subordinated to any other indebtedness
of Maker, provided, that nothing herein shall be construed to prohibit Maker
from incurring any secured indebtedness.

     11.  COSTS OF ENFORCEMENT.  The Maker agrees to pay on demand all costs of
collection, including attorneys' fees and costs, actually and reasonably
incurred by the Holder in enforcing the obligations of the Maker under this
Note.

     12.  WAIVERS.  No delay or omission on the part of the Holder in exercising
any right under this Note shall operate as a waiver of such right or of any
other right of such Holder, nor shall any delay, omission, or waiver on any one
occasion be deemed to bar or waive the same right or any other right on any
future occasion.  The Maker waives notices of presentment, demand, protest, and
notices of every other kind that relate to this Note.

                                       3
<PAGE>

     13.  EXCLUSION, MODIFICATION, AND AMENDMENT.  No term or provision of this
Note may be excluded, modified, or amended, except by a written instrument duly
executed on behalf of the Maker and Holder, and any such written instrument
shall expressly refer to this Note and shall set forth with specificity the term
or provision to be excluded, modified, or amended.

     14.  BUSINESS DAY.  Notwithstanding anything to the contrary herein, if any
payment of principal or interest is due on a day that is not a Business Day,
payment shall be made on the next succeeding Business Day, with the same effect
as if made on the day such payment was due, and no interest shall accrue thereon
for the period after such date.  A "Business Day" shall mean any day that is not
a Saturday, Sunday or day on which banking institutions in the Commonwealth of
Massachusetts are authorized or obligated by applicable law, regulation or
executive order to close.

     15.  GOVERNING LAW.  All rights and obligations hereunder shall be governed
by the laws of the Commonwealth of Massachusetts.

     16.  SEAL.  This Note is executed as an instrument under seal.

     IN WITNESS WHEREOF, the Maker has caused this Note to be executed in its
corporate name by the signature of its duly authorized officer.

                              CMGI, INC.


                              By: /s/ Andrew J. Hajducky III
                                  --------------------------
                                  Andrew J. Hajducky III
                                  Executive Vice President

                                       4

Source: OneCLE Business Contracts.