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                                                                   EXHIBIT 10.18

THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR
OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT
OR AN OPINION OF COUNSEL, REASONABLY SATISFACTORY TO THE CORPORATION AND ITS
COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.

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                            WARRANT TO PURCHASE STOCK

WARRANT TO PURCHASE 83,904        ISSUE DATE:              DECEMBER 3, 1999
SHARES OF THE CLASS A COMMON      EXPIRATION DATE:         DECEMBER 3, 2004
STOCK OF GREENFIELD ONLINE, INC.  INITIAL EXERCISE PRICE:  $7.15 PER SHARE

THIS WARRANT CERTIFIES THAT, for the agreed upon value of $1.00 and for other
good and valuable consideration, GREYROCK CAPITAL, A DIVISION OF BANC OF AMERICA
COMMERCIAL FINANCE CORPORATION ("Holder") is entitled to purchase the number of
fully paid and non-assessable shares of the Class A common stock (the "Shares")
of Greenfield Online, Inc., a Connecticut corporation (the "Company") at the
initial exercise price per Share (the "Warrant Price") all as set forth above
and as adjusted pursuant to Article 2 of this Warrant, subject to the provisions
and upon the terms and conditions set forth in this Warrant.

ARTICLE 1.   EXERCISE.

      1.1 METHOD OF EXERCISE. Holder may exercise this Warrant by delivering a
duly executed Notice of Exercise in substantially the form attached as Appendix
1 to the principal office of the Company. Unless Holder is exercising the
conversion right set forth in Section 1.2, Holder shall also deliver to the
Company a check for the aggregate Warrant Price for the Shares being purchased.

      1.2 CONVERSION RIGHT. In lieu of exercising this Warrant as specified in
Section 1.1, Holder may from time to time convert this Warrant, in whole or in
part, into a number of Shares determined by dividing (a) the aggregate fair
market value of the Shares or other securities otherwise issuable upon exercise
of this Warrant minus the aggregate Warrant Price of such Shares by (b) the fair
market value of one Share. The fair market value of the Shares shall be
determined pursuant Section 1.4.

      1.3 FAIR MARKET VALUE. If the Shares are traded in a public market, the
fair market value of the Shares shall be the closing price of the Shares (or the
closing price of the Company's stock into which the Shares are convertible)
reported for the business day immediately before Holder delivers its Notice of
Exercise to the Company. If the Shares are not traded in a public market, the
Board of Directors of the Company shall determine fair market value in its
reasonable good faith judgment. The foregoing notwithstanding, if Holder advises
the Board of Directors in writing that Holder disagrees with such determination,
then the Company and Holder shall promptly agree upon a reputable investment
banking firm to undertake such valuation. If the valuation of such investment
banking firm is greater than 110% of the amount determined by the Board of
Directors, then all fees and expenses of such investment banking firm shall be
paid by the Company. In all other circumstances, such fees and expenses shall be
paid by Holder.

      1.4 DELIVERY OF CERTIFICATE AND NEW WARRANT. Promptly after Holder
exercises or converts this Warrant, the Company shall deliver to Holder
certificates for the Shares acquired and, if this Warrant has not been fully
exercised or converted and has not expired, a new Warrant representing the
Shares not so acquired.

      1.5 REPLACEMENT OF WARRANTS. On receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and, in the case of loss, theft or destruction, on delivery of an
indemnity agreement reasonably satisfactory in form and amount to the Company
or, in the case of mutilation, on surrender and cancellation of this Warrant,
the Company at its expense shall execute and deliver, in lieu of this Warrant, a
new warrant of like tenor.

      1.6 REPURCHASE ON SALE, MERGER OR CONSOLIDATION OF THE COMPANY.

      1.6.1. "ACQUISITION". For the purpose of this Warrant, "Acquisition" means
any sale, license, or other disposition of all or substantially all of the
assets of the Company, or any reorganization, consolidation, or merger of the
Company where the holders of the Company's securities before the transaction
beneficially own less than 50% of the outstanding voting securities of the
surviving entity after the transaction.

      1.6.2. ASSUMPTION OF WARRANT. If upon the closing of any Acquisition the
successor entity assumes the obligations of this Warrant, then this Warrant
shall be exercisable for the same securities, cash, and property as would be
payable for the Shares issuable upon exercise of the unexercised portion of this
Warrant as if such Shares

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                                                       WARRANT TO PURCHASE STOCK
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were outstanding on the record date for the Acquisition and subsequent closing.
The Warrant Price shall be adjusted accordingly.

            1.6.3. NONASSUMPTION. If upon the closing of any Acquisition the
      successor entity does not assume the obligations of this Warrant and
      Holder has not otherwise exercised this Warrant in full, then the
      unexercised portion of this Warrant shall be deemed to have been
      automatically converted pursuant to Section 1.2 and thereafter Holder
      shall participate in the acquisition on the same terms as other holders of
      the same class of securities of the Company.

ARTICLE 2.   ADJUSTMENTS TO THE SHARES.

      2.1 STOCK DIVIDENDS, SPLITS, ETC. If the Company declares or pays a
dividend on its common stock (or the Shares if the Shares are securities other
than common stock) payable in common stock, or other securities, subdivides the
outstanding common stock into a greater amount of common stock, or, if the
Shares are securities other than common stock, subdivides the Shares in a
transaction that increases the amount of common stock into which the Shares are
convertible, then upon exercise of this Warrant, for each Share acquired, Holder
shall receive, without cost to Holder, the total number and kind of securities
to which Holder would have been entitled had Holder owned the Shares of record
as of the date the dividend or subdivision occurred.

      2.2 RECLASSIFICATION, EXCHANGE OR SUBSTITUTION. Upon any reclassification,
exchange, substitution, or other event that results in a change of the number
and/or class of the securities issuable upon exercise or conversion of this
Warrant, Holder shall be entitled to receive, upon exercise or conversion of
this Warrant, the number and kind of securities and property that Holder would
have received for the Shares if this Warrant had been exercised immediately
before such reclassification, exchange, substitution, or other event. Such an
event shall include any automatic conversion of the outstanding or issuable
securities of the Company of the same class or series as the Shares to common
stock pursuant to the terms of the Company's Articles of Incorporation upon the
closing of a registered public offering of the Company's common stock. The
Company or its successor shall promptly issue to Holder a new Warrant for such
new securities or other property. The new Warrant shall provide for adjustments
which shall be as nearly equivalent as may be practicable to the adjustments
provided for in this Article 2 including, without limitation, adjustments to the
Warrant Price and to the number of securities or property issuable upon exercise
of the new Warrant. The provisions of this Section 2.2 shall similarly apply to
successive reclassifications, exchanges, substitutions, or other events.

      2.3 ADJUSTMENTS FOR COMBINATIONS, ETC. If the outstanding Shares are
combined or consolidated, by reclassification or otherwise, into a lesser number
of shares, the Warrant Price shall be proportionately increased.

      2.4 ADJUSTMENTS FOR DILUTING ISSUANCES. The Warrant Price and the number
of Shares issuable upon exercise of this Warrant or, if the Shares are Preferred
Stock, the number of shares of common stock issuable upon conversion of the
Shares, shall be subject to adjustment, from time to time in the manner set
forth on Exhibit A.

      2.5 NO IMPAIRMENT. The Company shall not, by amendment of its Articles of
Incorporation or through a reorganization, transfer of assets, consolidation,
merger, dissolution, issue, or sale of securities or any other voluntary action,
avoid or seek to avoid the observance or performance of any of the terms to be
observed or performed under this Warrant by the Company, but shall at all times
in good faith assist in carrying out of all the provisions of this Article 2 and
in taking all such action as may be necessary or appropriate to protect Holder's
rights under this Article against impairment. If the Company takes any action
affecting the Shares or its common stock other than as described above that
adversely affects Holder's rights under this Warrant, the Warrant Price shall be
adjusted downward and the number of Shares issuable upon exercise of this
Warrant shall be adjusted upward in such a manner that the aggregate Warrant
Price of this Warrant is unchanged.

      2.6 FRACTIONAL SHARES. No fractional Shares shall be issuable upon
exercise or conversion of the Warrant and the number of Shares to be issued
shall be rounded down to the nearest whole Share. If a fractional share interest
arises upon any exercise or conversion of the Warrant, the Company shall
eliminate such fractional share interest by paying Holder amount computed by
multiplying the fractional interest by the fair market value of a full Share.

      2.7 CERTIFICATE AS TO ADJUSTMENTS. Upon each adjustment of the Warrant
Price, the Company at its expense shall promptly compute such adjustment, and
furnish Holder with a certificate of its Chief Financial Officer setting forth
such adjustment and the facts upon which such adjustment is based. The Company
shall, upon written request, furnish Holder a certificate setting forth the
Warrant Price in effect upon the date thereof and the series of adjustments
leading to such Warrant Price.

ARTICLE 3. REPRESENTATIONS AND COVENANTS OF THE COMPANY.

      3.1 REPRESENTATIONS AND WARRANTIES. The Company hereby represents and
warrants to the Holder as follows:

      (a) Shares which may be issued upon the exercise of the purchase right
represented by this Warrant, and all securities, if any, issuable upon
conversion of the Shares, shall, upon issuance, be duly authorized, validly
issued,

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fully paid and non-assessable, and free of any liens and encumbrances except for
restrictions on transfer provided for herein or under applicable federal and
state securities laws.

      (b) The capitalization of the Company at December 3, 1999, was as set
forth on Schedule 3.1(b) attached hereto, and on the issue date hereof the
Shares shall represent no less than 0.6% of the Company's common stock on a
fully diluted basis.

      3.2 NOTICE OF CERTAIN EVENTS. If the Company proposes at any time (a) to
declare any dividend or distribution upon its common stock, whether in cash,
property, stock, or other securities and whether or not a regular cash dividend;
(b) to offer for subscription pro rata to the holders of any class or series of
its stock any additional shares of stock of any class or series or other rights;
(c) to effect any reclassification or recapitalization of common stock; (d) to
merge or consolidate with or into any other corporation, or sell, lease,
license, or convey all or substantially all of its assets, or to liquidate,
dissolve or wind up; or (e) offer holders of registration rights the opportunity
to participate in an underwritten public offering of the company's securities
for cash, then, in connection with each such event, the Company shall give
Holder (1) at least 10 days prior written notice of the date on which a record
will be taken for such dividend, distribution, or subscription rights (and
specifying the date on which the holders of common stock will be entitled
thereto) or for determining rights to vote, if any, in respect of the matters
referred to in (c) and (d) above; (2) in the case of the matters referred to in
(c) and (d) above at least 10 days prior written notice of the date when the
same will take place (and specifying the date on which the holders of common
stock will be entitled to exchange their common stock for securities or other
property deliverable upon the occurrence of such event); and (3) in the case of
the matter referred to in (e) above, the same notice as is given to the holders
of such registration rights.

      3.3 INFORMATION RIGHTS. So long as the Holder holds this Warrant and/or
any of the Shares, the Company shall deliver to the Holder (a) promptly after
mailing, copies of all notices or other written communications to the
shareholders of the Company, (b) within ninety (90) days after the end of each
fiscal year of the Company, the annual audited financial statements of the
Company certified by independent public accountants of recognized standing or 10
days after the Company's receipt of the same from the independent CPAs,
whichever is later, and (c) within forty-five (45) days after the end of each of
the first three quarters of each fiscal year, the Company's quarterly, unaudited
financial statements.

      3.4 REGISTRATION UNDER SECURITIES ACT OF 1933, AS AMENDED. The Company
agrees that the Shares or, if the Shares are convertible into common stock of
the Company, such common stock, shall be subject to the registration rights set
forth on Exhibit B, if attached.

ARTICLE 4. MISCELLANEOUS.

      4.1 TERM: NOTICE OF EXPIRATION. This Warrant is exercisable, in whole or
in part, at any time and from time to time on or before the Expiration Date set
forth above. The Company shall give Holder written notice of Holder's right to
exercise this Warrant in the form attached as Appendix 2 not more than 90 days
and not less than 30 days before the Expiration Date. If the notice is not so
given, the Expiration Date shall automatically be extended until 30 days after
the date the Company delivers the notice to Holder.

      4.2 LEGENDS. This Warrant and the Shares (and the securities issuable,
directly or indirectly, upon conversion of the Shares, if any) shall be
imprinted with a legend in substantially the following form:

      THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, AND MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED WITHOUT AN
EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT OR AN OPINION OF COUNSEL
REASONABLY SATISFACTORY TO THE CORPORATION AND ITS COUNSEL THAT SUCH
REGISTRATION IS NOT REQUIRED.

      4.3 COMPLIANCE WITH SECURITIES LAWS ON TRANSFER. This Warrant and the
Shares issuable upon exercise of this Warrant (and the securities issuable,
directly or indirectly, upon conversion of the Shares, if any) may not be
transferred or assigned in whole or in part without compliance with applicable
federal and state securities laws by the transferor and the transferee
(including, without limitation, the delivery of investment representation
letters and legal opinions reasonably satisfactory to the Company, if reasonably
requested by the Company). In any event, no transfer of the Holder's rights
under this Warrant shall be authorized unless the transferee shall be assuming a
proportionate share of Holder's rights, duties and obligations under a certain
Loan and Security Agreement between the Company and Holder dated December 3,
1999.

      4.4 TRANSFER PROCEDURE. Subject to the provisions of Section 4.2 and 4.3,
Holder may transfer all or part of this Warrant or the Shares issuable upon
exercise of this Warrant (or the securities issuable, directly or indirectly,
upon conversion of the Shares, if any) by giving the Company notice of the
portion of the Warrant being transferred setting forth the name, address and
taxpayer identification number of the transferee and surrendering this Warrant
to the Company for reissuance to the transferee(s) (and Holder if applicable).
Unless the Company is filing financial information with the SEC pursuant to the
Securities Exchange Act of 1934, the

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Company shall have the right to refuse to transfer any portion of this Warrant
to any person who directly competes with the Company or any affiliate of any
person who competes directly with the Company or to any person who owns 5% or
more of the stock of any person who competes directly with the Company.

      4.5 NOTICES. All notices and other communications from the Company to the
Holder, or vice versa, shall be deemed delivered and effective when given
personally or mailed by first-class registered or certified mail, postage
prepaid, at such address as may have been furnished to the Company or the
Holder, as the case may be, in writing by the Company or such holder from time
to time.

      4.6 WAIVER. This Warrant and any term hereof may be changed, waived,
discharged or terminated only by an instrument in writing signed by the party
against which enforcement of such change, waiver, discharge or termination is
sought.

      4.7 ATTORNEYS FEES. In the event of any dispute between the parties
concerning the terms and provisions of this Warrant, the party prevailing in
such dispute shall be entitled to collect from the other party all costs
incurred in such dispute, including reasonable attorneys' fees.

      4.8 GOVERNING LAW. This Warrant shall be governed by and construed in
accordance with the laws of the State of New York, without giving effect to its
principles regarding conflicts of law.

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           GREENFIELD ONLINE, INC.


           BY_________________________________
                RUDY NADILO, PRESIDENT AND CEO


           BY_________________________________
                JONATHAN A. FLATOW, SECRETARY

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                                                       WARRANT TO PURCHASE STOCK
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