<PAGE>   1

                                                                     EXHIBIT 4.3

THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 AS
AMENDED, OR ANY STATE SECURITIES LAWS. THEY MAY NOT BE SOLD, OFFERED FOR SALE,
PLEDGED, OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT
RELATED THERETO OR AN OPINION OF COUNSEL (WHICH MAY BE COMPANY COUNSEL)
REASONABLY SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES
LAWS.

                                WARRANT AGREEMENT

              To Purchase Shares of the Series B Preferred Stock of

                                  EGROUPS, INC.

                 Dated as of June 23,1999 (the "Effective Date")

WHEREAS, eGroups, Inc., a Delaware corporation (the "Company") has entered into
a Master Lease Agreement dated as of June 23, 1999, Equipment Schedule No. VL-1
and VL-2 dated as of June 23, 1999, and related Summary Equipment Schedules
(collectively, the "Leases") with Comdisco, Inc., a Delaware corporation (the
"Warrantholder"); and

WHEREAS, the Company desires to grant to Warrantholder, in consideration for
such Leases, the right to purchase shares of its Series B Preferred Stock;

NOW, THEREFORE, in consideration of the Warrantholder executing and delivering
such Leases and in consideration of mutual covenants and agreements contained
herein, the Company and Warrantholder agree as follows:

1.       GRANT OF THE RIGHT TO PURCHASE PREFERRED STOCK.

The Company hereby grants to the Warrantholder, and the Warrantholder is
entitled, upon the terms and subject to the conditions hereinafter set forth, to
subscribe to and purchase, from the Company, such number of fully paid and
non-assessable shares of the Company's Series B Preferred Stock ("Preferred
Stock") equal to $60,000 divided by the Exercise Price. The Exercise Price shall
be the price per share of the Next Round of financing, provided such financing
is completed on or before December 1, 1999. In the event the Next Round is
completed after December 1, 1999, the Exercise Price shall be $1.43955 per
share. Next Round shall be defined as (i) preferred stock financing of at least
$2,000,000, (ii) the sale, conveyance disposal, or encumbrance of all or
substantially all of the Company's property or business or Company's merger into
or consolidation with any other corporation (other than a wholly-owned
subsidiary corporation).or any other transaction or series of related
transactions in which more than fifty percent (50%) of the voting power of
Company is disposed of ("Merger Event"), provided that a Merger Event shall not
apply to a merger effected exclusively for the purpose of changing the domicile
of the company or (iii) an initial public offering of the Company's Common Stock
which such public offering has been declared effective by the SEC.
Notwithstanding the foregoing, in the event the Next Round is a transaction as
defined in (ii) or (iii) above, the Exercise Price shall be the greater of (a) a
30% discount to the price per share in such



<PAGE>   2

financing or (b) $1.43955, The number and purchase price of such shares are
subject to adjustment as provided in Section 8 hereof.

2.       TERM OF THE WARRANT AGREEMENT.

Except as otherwise provided for herein, the term of this Warrant Agreement and
the right to purchase Preferred Stock as granted herein shall commence on the
Effective Date and shall be exercisable for a period of (i) five (5) years or
(ii) three (3) years from the effective date of the Company's initial public
offering, whichever is earlier.

Notwithstanding the term of this Warrant Agreement fixed pursuant to the above
paragraph, the right to purchase Preferred Stock as granted herein shall expire,
if not previously exercised immediately upon the closing of a merger or
consolidation of the Company with or into another corporation when the Company
is not the surviving corporation, or the sale of all or substantially all of the
Company's properties and assets to any other person (the "Merger") provided in
which Warrantholder realizes a value for its shares equal to or greater than
$4.31865 per share.

The Company shall notify the Warrantholder if the Merger is proposed in
accordance with the terms of 8(f) hereof, and if the Company fails to deliver
such written notice, then notwithstanding anything to the contrary in this
Warrant Agreement, the rights to purchase the Company's Preferred Stock shall
not expire until the Company complies with such notice provisions. Such notice
shall also contain such details of the proposed Merger as are reasonable in the
circumstances. If such closing does not take place, the Company shall promptly
notify the Warrantholder that such proposed transaction has been terminated, and
the Warrantholder may rescind any exercise of its purchase rights promptly after
such notice of termination of the proposed transaction If the exercise of
Warrants has occurred after the Company notified the Warrantholder that the
Merger was proposed. In the event of such rescission, the Warrants will continue
to be exercisable on the same terms and conditions contained herein.

3.        EXERCISE OF THE PURCHASE RIGHTS.

The purchase rights set forth in this Warrant Agreement are exercisable by the
Warrantholder, in whole or in part, at any time, or from time to time, prior to
the expiration of the term set forth in Section 2 above, by tendering to the
Company at its principal office a notice of exercise in the form attached hereto
as Exhibit I (the "Notice of Exercise"), duly completed and executed. Promptly
upon receipt of the Notice of Exercise and the payment of the purchase price in
accordance with the terms set forth below, and in no event later than twenty-one
(21) days thereafter, the Company shall issue to the Warrantholder a certificate
for the number of shares of Preferred Stock purchased and shall execute the
acknowledgment of exercise in the form attached hereto as Exhibit II (the
"Acknowledgment of Exercise") indicating the number of shares which remain
subject to future purchases, if any.

The Exercise Price may be paid at the Warrantholder's election either (i) by
cash or check, or (ii) by surrender of Warrants ("Net Issuance") as determined
below. If the Warrantholder elects the Net Issuance method, the Company will
issue Preferred Stock in accordance with the following formula:


X = Y(A-B)
----------


                                      -2-
<PAGE>   3

       A

Where:       X = the number of shares of Preferred Stock to be issued to the
Warrantholder.

             Y = the number of shares of Preferred Stock requested to be
exercised under this Warrant Agreement.

             A = the fair market value of one (1) share of Preferred Stock.

             B = the Exercise Price.

For purposes of the above calculation, current fair market value of Preferred
Stock shall mean with respect to each share of Preferred Stock:

(i) if the exercise is in connection with an initial public offering of the
Company's Common Stock, and if the Company's Registration Statement relating to
such public offering has been declared effective by the SEC, then the fair
market value per share shall be the product of (x) the initial "Price to Public"
specified in the final prospectus with respect to the offering and (y) the
number of shares of Common Stock into which each share of Preferred Stock is
convertible at the time of such exercise;

(ii) if this Warrant is exercised after, and not in connection with the
Company's initial public offering,and:

(a) if traded on a securities exchange, the fair market value shall be deemed to
be the product of (x) the average of the closing prices over a five (5) day
period ending three days before the day the current fair market value of the
securities is being determined and (y) the number of shares of Common Stock into
which each share of Preferred Stock is convertible at the time of such exercise;
or

(b) if actively traded over-the-counter, the fair market value shall be deemed
to be the product of (x) the average of the closing bid and asked prices quoted
on the NASDAQ system (or similar system) over the five (5) day period ending
three days before the day the current fair market value of the securities is
being determined and (y) the number of shares of Common Stock into which each
share of Preferred Stock is convertible at the time of such exercise;

(iii) if at any time the Common Stock is not listed on any securities exchange
or quoted in the NASDAQ System or the over-the-counter market, the current fair
market value of Preferred Stock shall be the product of (x) the highest price
per share which the Company could obtain from a willing buyer (not a current
employee or director) for shares of Common Stock sold by the Company, from
authorized but unissued shares, as determined in good faith by its Board of
Directors and (y) the number of shares of Common Stock into which each share of
Preferred Stock is convertible at the time of such exercise, unless the Company
shall become subject to a merger, acquisition or other consolidation pursuant to
which the Company is not the surviving party, in which case the fair market
value of Preferred Stock shall be deemed to be the value received by the holders
of the Company's Preferred Stock on a common equivalent basis pursuant to such
merger or acquisition.



                                      -3-
<PAGE>   4

Upon partial exercise by either cash or Net Issuance, the Company shall promptly
issue an amended Warrant Agreement representing the remaining number of shares
purchasable hereunder. All other terms and conditions of such amended Warrant
Agreement shall be identical to those contained herein, including, but not
limited to the Effective Date hereof.

4.        RESERVATION OF SHARES.

(a) Authorization and Reservation of Shares. During the term of this Warrant
Agreement, the Company will at all times have authorized and reserved a
sufficient number of shares of its Preferred Stock to provide for the exercise
of the rights to purchase Preferred Stock as provided for herein.

(b) Registration or Listing. If any shares of Preferred Stock required to be
reserved hereunder require registration with or approval of any governmental
authority under any Federal or State law (other than any registration under the
Securities Act of 1933, as amended ("1933 Act"), as then in effect, or any
similar Federal statute then enforced, or any state securities law, required by
reason of any transfer involved in such conversion), or listing on any domestic
securities exchange, before such shares may be issued upon conversion, the
Company will, at its expense and as expeditiously as possible, use its best
efforts to cause such shares to be duly registered, listed or approved for
listing on such domestic securities exchange, as the case may be.

5.        NO FRACTIONAL SHARES OR SCRIP.

No fractional shares or scrip representing fractional shares shall be issued
upon the exercise of the Warrant, but in lieu of such fractional shares the
Company shall make a cash payment therefor upon the basis of the Exercise Price
then in effect.

6.        NO RIGHTS AS SHAREHOLDER.

This Warrant Agreement does not entitle the Warrantholder to any voting rights
or other rights as a shareholder of the Company prior to the exercise of the
Warrant.

7.        WARRANTHOLDER REGISTRY.

The Company shall maintain a registry showing the name and address of the
registered holder of this Warrant Agreement.

8.        ADJUSTMENT RIGHTS.

The purchase price per share and the number of shares of Preferred Stock
purchasable hereunder are subject to adjustment, as follows:

(a) Merger and Sale of Assets. If at any time there shall be a capital
reorganization of the shares of the Company's stock (other than a combination,
reclassification, exchange or subdivision of shares otherwise provided for
herein), or a merger or consolidation of the Company with or into another
corporation whether or not the Company is the surviving corporation, or the sale
of all or substantially all of the Company's properties and assets to any other
person (hereinafter referred to as a "Merger Event"), then, as a part of such
Merger Event, lawful provision shall be made so that the



                                      -4-
<PAGE>   5

Warrantholder shall thereafter be entitled to receive, upon exercise of the
Warrant, the number of shares of preferred stock or other securities of the
successor corporation resulting from such Merger Event, equivalent in value to
that which would have been issuable if Warrantholder had exercised this Warrant
immediately prior to the Merger Event. In any such case, appropriate adjustment
(as determined in good faith by the Company's Board of Directors) shall be made
in the application of the provisions of this Warrant Agreement with respect to
the rights and interest of the Warrantholder after the Merger Event to the end
that the provisions of this Warrant Agreement (including adjustments of the
Exercise Price and number of shares of Preferred Stock purchasable) shall be
applicable to the greatest extent possible.

(b) Reclassification of Shares. If the Company at any time shall, by
combination, reclassification, exchange or subdivision of securities or
otherwise, change any of the securities as to which purchase rights under this
Warrant Agreement exist into the same or a different number of securities of any
other class or classes, this Warrant Agreement shall thereafter represent the
right to acquire such number and kind of securities as would have been issuable
as the result of such change with respect to the securities which were subject
to the purchase rights under this Warrant Agreement immediately prior to such
combination, reclassification, exchange, subdivision or other change.

(c) Subdivision or Combination of Shares. If the Company at any time shall
combine or subdivide its Preferred Stock, the Exercise Price shall be
proportionately decreased in the case of a subdivision, or proportionately
increased in the case of a combination.

(d) Stock Dividends. If the Company at any time shall pay a dividend payable in,
or make any other distribution (except any distribution specifically provided
for in the foregoing subsections (a) or (b)) of the Company's stock, then the
Exercise Price shall be adjusted, from and after the record date of such
dividend or distribution, to that price determined by multiplying the Exercise
Price in effect immediately prior to such record date by a fraction (i) the
numerator of which shall be the total number of all shares of the Company's
stock outstanding immediately prior to such dividend or distribution, and (ii)
the denominator of which shall be the total number of all shares of the
Company's stock outstanding immediately after such dividend or distribution. The
Warrantholder shall thereafter be entitled to purchase, at the Exercise Price
resulting from such adjustment, the number of shares of Preferred Stock
(calculated to the nearest whole share) obtained by multiplying the Exercise
Price in effect immediately prior to such adjustment by the number of shares of
Preferred Stock issuable upon the exercise hereof immediately prior to such
adjustment and dividing the product thereof by the Exercise Price resulting from
such adjustment.

(e) Antidilution Rights. Additional antidilution rights applicable to the
Preferred Stock purchasable hereunder are as set forth in the Company's
Certificate of Incorporation, as amended through the Effective Date, a true and
complete copy of which is attached hereto as Exhibit IV (the "Charter"). The
Company shall promptly provide the Warrantholder with any restatement,
amendment, modification or waiver of the Charter. The Company shall provide
Warrantholder with prior written notice of any issuance of its stock or other
equity security to occur after the Effective Date of this Warrant, which notice
shall include (a) the price at which such stock or security is to be sold, (b)
the number of shares to be issued, and (c) such other information as necessary
for Warrantholder to determine if a dilutive event has occurred.



                                      -5-
<PAGE>   6

(f) Notice of Adjustments. If: (i) the Company shall declare any dividend or
distribution upon its stock, whether in cash, property, stock or other
securities; (ii) the Company shall offer for subscription prorata to the holders
of any class of its Preferred or other convertible stock any additional shares
of stock of any class or other rights; (iii) there shall be any Merger Event;
(iv) there shall be an initial public offering; or (v) there shall be any
voluntary dissolution, liquidation or winding up of the Company; then, in
connection with each such event, the Company shall send to the Warrantholder:
(A) at least ten (10) days' prior written notice of the date on which the books
of the Company shall close or a record shall be taken for such dividend,
distribution, subscription rights (specifying the date on which the holders of
Preferred Stock shall be entitled thereto) or for determining rights to vote in
respect of such Merger Event, dissolution, liquidation or winding up; (B) in the
case of any such Merger Event, dissolution, liquidation or winding up, at least
ten (10) days' prior written notice of the date when the same shall take place
(and specifying the date on which the holders of Preferred Stock shall be
entitled to exchange their Preferred Stock for securities or other property
deliverable upon such Merger Event, dissolution, liquidation or winding up); and
(C) in the case of a public offering, the Company shall give the Warrantholder
at least ten (10) days written notice prior to the effective date thereof.

Each such written notice shall set forth, in reasonable detail, (i) the event
requiring the adjustment, (ii) the amount of the adjustment, (iii) the method by
which such adjustment was calculated, (iv) the Exercise Price, and (v) the
number of shares subject to purchase hereunder after giving effect to such
adjustment, and shall be given by first class mail, postage prepaid, addressed
to the Warrantholder, at the address as shown on the books of the Company.

(g) Timely Notice. Failure to timely provide such notice required by subsection
(f) above shall entitle Warrantholder to retain the benefit of the applicable
notice period notwithstanding anything to the contrary contained in any
insufficient notice received by Warrantholder. The notice period shall begin on
the date Warrantholder actually receives a written notice containing all the
information specified above.

9.       REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE COMPANY.

(a) Reservation of Preferred Stock. The Preferred Stock issuable upon exercise
of the Warrantholders rights has been duly and validly reserved and, when issued
in accordance with the provisions of this Warrant Agreement, will be validly
issued, fully paid and non-assessable, and will be free of any taxes, liens,
charges or encumbrances of any nature whatsoever; provided, however, that the
Preferred Stock issuable pursuant to this Warrant Agreement may be subject to
restrictions on transfer under state and/or Federal securities laws. The Company
has made available to the Warrantholder true, correct and complete copies of its
Charter and Bylaws, as amended. The issuance of certificates for shares of
Preferred Stock upon exercise of the Warrant Agreement shall be made without
charge to the Warrantholder for any issuance tax in respect thereof, or other
cost incurred by the Company in connection with such exercise and the related
issuance of shares of Preferred Stock. The Company shall not be required to pay
any tax which may be payable in respect of any transfer involved and the
issuance and delivery of any certificate in a name other than that of the
Warrantholder.

(b) Due Authority. The execution and delivery by the Company of this Warrant
Agreement and the performance of all obligations of the Company hereunder,
including the issuance to



                                      -6-
<PAGE>   7

Warrantholder of the right to acquire the shares of Preferred Stock, have been
duly authorized by all necessary corporate action on the part of the Company,
and the Leases and this Warrant Agreement are not inconsistent with the
Company's Charter or Bylaws, do not contravene any law or governmental rule,
regulation or order applicable to it, do not and will not contravene any
provision of, or constitute a default under, any indenture, mortgage, contract
or other instrument to which it is a party or by which it is bound, and the
Leases and this Warrant Agreement constitute legal, valid and binding agreements
of the Company, enforceable in accordance with their respective terms.

(c) Consents and Approvals. No consent or approval of, giving of notice to,
registration with, or taking of any other action in respect of any state,
Federal or other governmental authority or agency is required with respect to
the execution, delivery and performance by the Company of its obligations under
this Warrant Agreement, except for the filing of notices pursuant to Regulation
D under the 1933 Act and any filing required by applicable state securities law,
which filings will be effective by the time required thereby.

(d) Issued Securities. All issued and outstanding shares of Common Stock,
Preferred Stock or any other securities of the Company have been duly authorized
and validly issued and are fully paid and nonassessable. All outstanding shares
of Common Stock, Preferred Stock and any other securities were issued in full
compliance with all Federal and state securities laws. In addition:

(i) The authorized capital of the Company consists of (A) 20,000,000 shares of
Common Stock, of which 5,812,399 shares are issued and outstanding; (B)
1,620,000 shares of Series A Preferred Stock, of which 1,620,000 shares are
issued and outstanding and are convertible into 1,620,000 shares of Common Stock
at $0.50 per share; and (C) 3,600,000 shares of Series B Preferred Stock, of
which 3,556,772 shares are issued and outstanding and convertible into 3,556,772
shares of Common Stock at $1.43955 per share.

(ii) The Company has reserved (A) 1,900,000 shares of Common Stock for issuance
under its 1998 Stock Option Plan, under which 768,450 options are outstanding.
There are no other options, warrants, conversion privileges or other rights
presently outstanding to purchase or otherwise acquire any authorized but
unissued shares of the Company's capital stock or other securities of the
Company.

(iii) Except as set forth in the First Amended and Restated Investors Rights
Agreement dated December 17, 1998 (the "Rights Agreement"), no shareholder of
the Company has preemptive rights to purchase new issuances of the Company's
capital stock.

(e) Insurance. The Company has in full force and effect insurance policies, with
extended coverage, insuring the Company and its property and business against
such losses and risks, and in such amounts, as are customary for corporations
engaged in a similar business and similarly situated and as otherwise may be
required pursuant to the terms of any other contract or agreement.

M Other Commitments to Register Securities. Except as set forth in the Rights
Agreement, the Company is not, pursuant to the terms of any other agreement
currently in existence, under any obligation to register under the 1933 Act any
of its presently outstanding securities or any of its securities which may
hereafter be issued.



                                      -7-
<PAGE>   8

(g) Exempt Transaction. Subject to the accuracy of the Warrantholder's
representations in Section 10 hereof, the issuance of the Preferred Stock upon
exercise of this Warrant will constitute a transaction exempt from (i) the
registration requirements of Section 5 of the 1933 Act, in reliance upon Section
4(2) thereof, and (ii) the qualification requirements of the applicable state
securities laws.

(h) Compliance with Rule 144. At the written request of the Warrantholder, who
proposes to sell Preferred Stock issuable upon the exercise of the Warrant in
compliance with Rule 144 promulgated by the Securities and Exchange Commission,
the Company shall furnish to the Warrantholder, within ten days after receipt of
such request, a written statement confirming the Company's compliance with the
filing requirements of the Securities and Exchange Commission as set forth in
such Rule, as such Rule may be amended from time to time.

10.       REPRESENTATIONS AND COVENANTS OF THE WARRANTHOLDER.

This Warrant Agreement has been entered into by the Company in reliance upon the
following representations and covenants of the Warrantholder:

(a) Investment Purpose. The right to acquire Preferred Stock or the Preferred
Stock issuable upon exercise of the Warrantholder's rights contained herein will
be acquired for investment and not with a view to the sale or distribution of
any part thereof, and the Warrantholder has no present intention of selling or
engaging in any public distribution of the same except pursuant to a
registration or exemption.

(b) Private Issue. The Warrantholder understands (i) that the Preferred Stock
issuable upon exercise of this Warrant is not registered under the 1933 Act or
qualified under applicable state securities laws on the ground that the issuance
contemplated by this Warrant Agreement will be exempt from the registration and
qualifications requirements thereof, and (ii) that the Company's reliance on
such exemption is predicated on the representations set forth in this Section
10.

(c) Disposition of Warrantholder's Rights. In no event will the Warrantholder
make a disposition of any of its rights to acquire Preferred Stock or Preferred
Stock issuable upon exercise of such rights unless and until (i) it shall have
notified the Company of the proposed disposition, and (ii) if requested by the
Company, it shall have furnished the Company with an opinion of counsel (which
counsel may either be inside or outside counsel to the Warrantholder)
satisfactory to the Company and its counsel to the effect that (A) appropriate
action necessary for compliance with the 1933 Act has been taken, or (B) an
exemption from the registration requirements of the 1933 Act is available.
Notwithstanding the foregoing, the restrictions imposed upon the transferability
of any of its rights to acquire Preferred Stock or Preferred Stock issuable on
the exercise of such rights do not apply to transfers from the beneficial owner
of any of the aforementioned securities to its nominee or from such nominee to
its beneficial owner, and shall terminate as to any particular share of
Preferred Stock when (1) such security shall have been effectively registered
under the 1933 Act and sold by the holder thereof in accordance with such
registration or (2) such security shall have been sold without registration in
compliance with Rule 144 under the 1933 Act, or (3) a letter shall have been
issued to the Warrantholder at its request by the staff of the Securities and
Exchange Commission or a ruling shall have been issued to the Warrantholder at
its request by such Commission stating that no action shall be recommended by
such staff or taken by such Commission, as the case may be, if



                                      -8-
<PAGE>   9

such security is transferred without registration under the 1933 Act in
accordance with the conditions set forth in such letter or ruling and such
letter or ruling specifies that no subsequent restrictions on transfer are
required. Whenever the restrictions imposed hereunder shall terminate, as
hereinabove provided, the Warrantholder or holder of a share of Preferred Stock
then outstanding as to which such restrictions have terminated shall be entitled
to receive from the Company, without expense to such holder, one or more new
certificates for the Warrant or for such shares of Preferred Stock not bearing
any restrictive legend.

(d) Financial Risk. The Warrantholder has such knowledge and experience in
financial and business matters as to be capable of evaluating the merits and
risks of its investment, and has the ability to bear the economic risks of its
investment.

(e) Risk of No Registration. The Warrantholder understands that if the Company
does not register with the Securities and Exchange Commission pursuant to
Section 12 of the 1934 Act (the "l 934 Act" ), or file reports pursuant to
Section 15(d), of the 1934 Act, or if a registration statement covering the
securities under the 1933 Act is not in effect when it desires to sell (i) the
rights to purchase Preferred Stock pursuant to this Warrant Agreement, or (ii)
the Preferred Stock issuable upon exercise of the right to purchase, it may be
required to hold such securities for an indefinite period. The Warrantholder
also understands that any sale of its rights of the Warrantholder to purchase
Preferred Stock or Preferred Stock which might be made by it in reliance upon
Rule 144 under the 1933 Act may be made only in accordance with the terms and
conditions of that Rule.

(f) Accredited Investor. Warrantholder is an "accredited investor" within the
meaning of the Securities and Exchange Rule 501 of Regulation D, as presently in
effect.

11.      TRANSFERS.

Subject to the terms and conditions contained in Section 10 hereof, this Warrant
Agreement and all rights hereunder are transferable in whole or in part by the
Warrantholder and any successor transferee, provided, however, in no event shall
the number of transfers of the rights and interests in all of the Warrants
exceed three (3) transfers. The transfer shall be recorded on the books of the
Company upon receipt by the Company of a notice of transfer in the form attached
hereto as Exhibit III (the 'Transfer Notice"), at its principal offices and the
payment to the Company of all transfer taxes and other governmental charges
imposed on such transfer.

12.      MARKET STANDOFF.

Warrantholder hereby agrees that, during the period of duration (up to, but not
exceeding, one hundred eighty (180) days) specified by the Company and an
underwriter of Common Stock or other securities of the Company, following the
effective date of a registration statement of the Company filed under the Act,
it shall not, to the extent requested by the Company and such underwriter,
directly or indirectly sell, offer to sell, contract to sell(including, without
limitation, any short sale), grant any option to purchase or otherwise transfer
or dispose of (other than to donees who agree to be similarly bound) any
securities of the Company held by it at any time during such period except
Common Stock included in such registration; provided, however, that:



                                      -9-
<PAGE>   10

(a) such agreement shall be applicable only to the first such registration
statement of the Company which covers Common Stock (or other securities) to be
sold on its behalf to the public in an underwritten offering; and

(b) all officers and directors of the Company, all one-percent security holders,
and all other persons with registration rights enter into similar agreements.

In order to enforce the foregoing covenant, the Company may impose stop
-transfer instructions with respect to the securities of each shareholder until
the end of such period, and Warrantholder agrees that, if so requested,
Warrantholder will execute an agreement in the form provided by the underwriter
containing terms which are essentially consistent with the provisions of this
Section 12.

Notwithstanding the foregoing, the obligations described in this Section 12
shall not apply to a registration relating solely to employee benefit plans on
Form S-1 or Form S-8 or similar forms which may be promulgated in the future, or
a registration relating solely to an SEC Rule 145 transaction on Form S-4 or
similar forms which may be promulgated in the future.

13.      MISCELLANEOUS.

(a) Effective Date. The provisions of this Warrant Agreement shall be construed
and shall be given effect in all respects as if it had been executed and
delivered by the Company on the date hereof. This Warrant Agreement shall be
binding upon any successors or assigns of the Company.

(b) Attorney's Fees. In any litigation, arbitration or court proceeding between
the Company and the Warrantholder relating hereto, the prevailing party shall be
entitled to attorneys' fees and expenses and all costs of proceedings incurred
in enforcing this Warrant Agreement.

(c) Goveminq Law. This Warrant Agreement shall be governed by and construed for
all purposes under and in accordance with the laws of the State of Illinois.

(d) Counterparts. This Warrant Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

(e) Notices. Any notice required or permitted hereunder shall be given in
writing and shall be deemed effectively given upon personal delivery, facsimile
transmission (provided that the original is sent by personal delivery or mail as
hereinafter set forth) or seven (7) days after deposit in the United States
mail, by registered or certified mail, addressed (i) to the Warrantholder at
6111 North River Road, Rosemont, Illinois 60018, Attention: Venture Lease
Administration, cc: Legal Department, Attention: General Counsel, (and/or, if by
facsimile, (847) 518-5465 and (847) 518-5088) and (ii) to the Company at 520
Third Street, Suite 225, San Francisco, CA 94107, Attention: Carl Page (and/or
if by facsimile, (415) 449-3594) cc: Perkins Coie, 135 Commonwealth Drive, Menlo
Park, CA, 94025, Attention: Ralph L Arnheim, III or at such other address as any
such party may subsequently designate by written notice to the other party.

(f) Remedies. In the event of any default hereunder, the non-defaulting party
may proceed to protect and enforce its rights either by suit in equity and/or by
action at law, including but not limited to an action for damages as a result of
any such default, and/or an action for specific performance for



                                      -10-
<PAGE>   11

any default where Warrantholder will not have an adequate remedy at law and
where damages will not be readily ascertainable. The Company expressly agrees
that it shall not oppose an application by the Warrantholder or any other person
entitled to the benefit of this Agreement requiring specific performance of any
or all provisions hereof or enjoining the Company from continuing to commit any
such breach of this Agreement.

(g) No Impairment of Rights. The Company will not, by amendment of its Charter
or through any other means, avoid or seek to avoid the observance or performance
of any of the terms of this Warrant, but will at all times in good faith assist
in the carrying out of all such terms and in the taking of all such actions as
may be necessary or appropriate in order to protect the rights of the
Warrantholder against impairment.

(h) Survival. The representations, warranties, covenants and conditions of the
respective parties contained herein or made pursuant to this Warrant Agreement
shall survive the execution and delivery of this Warrant Agreement.

(i) Severability. In the event any one or more of the provisions of this Warrant
Agreement shall for any reason be held invalid, illegal or unenforceable, the
remaining provisions of this Warrant Agreement shall be unimpaired, and the
invalid, illegal or unenforceable provision shall be replaced by a mutually
acceptable valid, legal and enforceable provision, which comes closest to the
intention of the parties underlying the invalid, illegal or unenforceable
provision.

(j) Amendments. Any provision of this Warrant Agreement may be amended by a
written instrument signed by the Company and by the Warrantholder.

(k) Additional Documents. The Company, upon execution of this Warrant Agreement,
shall provide the Warrantholder with certified resolutions with respect to the
representations, warranties and covenants set forth in subparagraphs (a) through
(d), (f) and (g) of Section 9 above. If the purchase price for the Leases
referenced in the preamble of this Warrant Agreement exceeds $1,000,000, the
Company will also provide Warrantholder with an opinion from the Company's
counsel with respect to those same representations, warranties and covenants.
The Company shall also supply such other documents as the Warrantholder may from
time to time reasonably request.

IN WITNESS WHEREOF, the parties hereto have caused this Warrant Agreement to be
executed by its officers thereunto duly authorized as of the Effective Date.

Company: EGROUPS, INC.

By:

Title:

Warrantholder: COMDISCO, INC.

By:

Title:



                                      -11-