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                                                                     Exhibit 4.9


                                FORM OF WARRANT


THIS WARRANT AND THE SHARES OF COMMON STOCK ISSUABLE UPON EXERCISE OF THIS
WARRANT HAVE BEEN ACQUIRED FOR INVESTMENT PURPOSES ONLY AND MAY NOT BE
TRANSFERRED UNTIL (i) A REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933,
AS AMENDED (THE "SECURITIES ACT") SHALL HAVE BECOME EFFECTIVE WITH RESPECT
THERETO OR (ii) RECEIPT BY THINKING TOOLS, INC. OF AN OPINION OF COUNSEL
REASONABLY SATISFACTORY TO THINKING TOOLS, INC. TO THE EFFECT THAT REGISTRATION
UNDER THE SECURITIES ACT IS NOT REQUIRED IN CONNECTION WITH SUCH PROPOSED
TRANSFER NOR IS SUCH TRANSFER IN VIOLATION OF ANY APPLICABLE STATE SECURITIES
LAWS. THIS LEGEND SHALL BE ENDORSED UPON ANY WARRANT ISSUED IN EXCHANGE FOR THIS
WARRANT OR ANY SHARES OF COMMON STOCK ISSUABLE UPON EXERCISE OF THIS WARRANT.


                        WARRANT TO PURCHASE COMMON STOCK

                                       OF

                              THINKING TOOLS, INC.



         This is to Certify That, FOR VALUE RECEIVED, AdSmart Corporation, or
assigns ("Holder"), is entitled to purchase, subject to the provisions of this
Warrant, from StartFree.com, Inc., a Delaware corporation ("Company"), 1,262,275
fully paid, validly issued and nonassessable shares of Common Stock, par value
$.001 per share ("Common Stock"), of Thinking Tools, Inc. ("Thinking Tools") at
a price of $.01 per share (the "Exercise Price"). The number of shares of Common
Stock to be received upon the exercise of this Warrant and the price to be paid
for each share of Common Stock may be adjusted from time to time as hereinafter
set forth. The shares of Common Stock deliverable upon such exercise, and as
adjusted from time to time, are hereinafter sometimes referred to as "Warrant
Shares" and the exercise price of a share of Common Stock in effect at any time
and as adjusted from time to time is hereinafter sometimes referred to as the
"Exercise Price".

         (a) EXERCISE OF WARRANT.

             (1) This Warrant may be exercised until May __, 2005 as follows:
(i) 500,400 shares of Common Stock are exercisable as of the date of this
Warrant, (ii) an additional 584,399 shares of Common Stock are exercisable on
the earlier of (y) 61 days after the date that the shares of Series A Preferred
Stock of Thinking Tools owned by Tritium Network, Inc. are converted into Common
Stock or (z) two years after the date of this Warrant; and (iii) an additional
177,476 shares of Common Stock are exercisable from time to time upon the
written request of the Holder if, as a result of such exercise, the Holder
beneficially own in excess of five percent (5%) or more of the outstanding
Common Stock; provided, however, that if the date of the exercise of this
Warrant falls on a day on which banking institutions in the State of New York
are authorized by law to close, then the date of such exercise shall be on the
next succeeding day which shall not be such a day. This Warrant may be exercised
by presentation and surrender hereof to the Company at its principal office,
with the Purchase Form annexed hereto duly executed and accompanied by payment
of the Exercise Price for the number of Warrant Shares





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specified in such form. As soon as practicable after each such exercise of the
Warrant, but not later than seven (7) days from the date of such exercise, the
Company shall cause to be delivered to the Holder a certificate or certificate
for the Warrant Shares issuable upon such exercise, registered in the name of
the Holder or its designee. If this Warrant should be exercised in part only,
the Company shall, upon surrender of this Warrant for cancellation, cause to be
executed and delivered a new Warrant evidencing the rights of the Holder thereof
to purchase the balance of the Warrant Shares purchasable thereunder. Upon
receipt by the Company of this Warrant at its office in proper form for
exercise, the Holder shall be deemed to be the holder of record of the shares of
Common Stock issuable upon such exercise, notwithstanding that the stock
transfer books of Thinking Tools shall then be closed or that certificates
representing such shares of Common Stock shall not then be physically delivered
to the Holder.

             (2) Subject to Section (a)(1) of this Warrant, at any time during
the period that this Warrant is exercisable in accordance with Section (a)(1)
of this Warrant, the Holder may, at its option, exchange this Warrant, in whole
or in part (a "Warrant Exchange"), into the number of Warrant Shares determined
in accordance with this Section (a)(2), by surrendering this Warrant at the
principal office of the Company accompanied by a notice stating such Holder's
intent to effect such exchange, the number of Warrant Shares to be exchanged
and the date on which the Holder requests that such Warrant Exchange occur
(the "Notice of Exchange"). The Warrant Exchange shall take place on the date
specified in the Notice of Exchange or, if later, the date the Notice of
Exchange is received by the Company (the "Exchange Date"). Certificates for the
shares issuable upon such Warrant Exchange and, if applicable, a new warrant of
like tenor evidencing the balance of the shares remaining subject to this
Warrant, shall be issued as of the Exchange Date and delivered to the Holder
within seven (7) days following the Exchange Date. In connection with any
Warrant Exchange, this Warrant shall represent the right to subscribe for and
acquire the number of Warrant Shares (rounded to the next highest integer) equal
to (i) the number of Warrant Shares specified by the Holder in its Notice of
Exchange (the "Total Number") less (ii) the number of Warrant Shares equal to
the quotient obtained by dividing (A) the product of the Total Number and the
existing Exercise Price by (B) the current market value of a share of Common
Stock. Current market value shall have the meaning set forth Section (c) below,
except that for purposes hereof, the date of exercise, as used in such Section
(c), shall mean the Exchange Date.

         (b) RESERVATION OF SHARES. Thinking Tools shall at all times reserve
for issuance and/or delivery upon exercise of this Warrant such number of shares
of its Common Stock as shall be required for issuance and delivery upon exercise
of the Warrants.

         (c) FRACTIONAL SHARES. No fractional shares or script representing
fractional shares shall be issued upon the exercise of this Warrant. With
respect to any fraction of a share called for upon any exercise hereof, Thinking
Tools shall pay to the Holder an amount in cash equal to such fraction
multiplied by the current market value of a share, determined as follows:

             (1) If the Common Stock is listed on a national securities exchange
         or admitted to unlisted trading privileges on such exchange or listed
         for trading on the Nasdaq National Market, the current market value
         shall be the last reported


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         sale price of the Common Stock on such exchange or market on the last
         business day prior to the date of exercise of this Warrant or if no
         such sale is made on such day, the average closing bid and asked prices
         for such day on such exchange or market; or

             (2) If the Common Stock is not so listed or admitted to unlisted
         trading privileges, but is traded on the Nasdaq Small Cap Market, the
         current Market Value shall be the average of the closing bid and asked
         prices for such day on such market and if the Common Stock is not so
         traded, the current market value shall be the mean of the last reported
         bid and asked prices reported by the National Quotation Bureau, Inc. on
         the last business day prior to the date of the exercise of this
         Warrant; or

             (3) If the Common Stock is not so listed or admitted to unlisted
         trading privileges and bid and asked prices are not so reported, the
         current market value shall be an amount, not less than book value
         thereof as at the end of the most recent fiscal year of Thinking Tools
         ending prior to the date of the exercise of the Warrant, determined in
         such reasonable manner as may be prescribed by the Board of Directors
         of Thinking Tools.

         (d) EXCHANGE, TRANSFER, ASSIGNMENT OR LOSS OF WARRANT. This Warrant is
exchangeable, without expense, at the option of the Holder, upon presentation
and surrender hereof to the Company for other warrants of different
denominations entitling the holder thereof to purchase in the aggregate the same
number of shares of Common Stock purchasable hereunder. This Warrant is not
transferable (other than by will or pursuant to the laws of descent and
distribution). Upon surrender of this Warrant to the Company at its principal
office with the Assignment Form annexed hereto duly executed and funds
sufficient to pay any transfer tax, the Company shall, without charge, cause to
be executed and delivered a new Warrant in the name of the assignee named in
such instrument of assignment and this Warrant shall promptly be cancelled. This
Warrant may be divided or combined with other warrants which carry the same
rights upon presentation hereof at the principal office of the Company together
with a written notice specifying the names and denominations in which new
Warrants are to be issued and signed by the Holder hereof. The term "Warrant" as
used herein includes any Warrants into which this Warrant may be divided or
exchanged. Upon receipt by the Company of evidence satisfactory to it of the
loss, theft, destruction or mutilation of this Warrant, and (in the case of
loss, theft or destruction) of reasonably satisfactory indemnification, and upon
surrender and cancellation of this Warrant, if mutilated, the Company will cause
to be executed and delivered a new Warrant of like tenor and date. Any such new
Warrant executed and delivered shall constitute an additional contractual
obligation on the part of the Company, whether or not this Warrant so lost,
stolen, destroyed, or mutilated shall be at any time enforceable by anyone.

         (e) RIGHTS OF THE HOLDER. The Holder shall not, by virtue hereof, be
entitled to any rights of a shareholder in Thinking Tools, either at law or
equity, and the rights of




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the Holder are limited to those expressed in the Warrant and are not enforceable
against the Thinking Tools except to the extent set forth herein.

         (f) ANTI-DILUTION PROVISIONS. The Exercise Price in effect at any time
and the number and kind of securities purchasable upon the exercise of the
Warrants shall be subject to adjustment from time to time upon the happening of
certain events as follows:

             (1) In case Thinking Tools shall (i) declare a dividend or make a
         distribution on its outstanding shares of Common Stock in shares of
         Common Stock, (ii) subdivide or reclassify its outstanding shares of
         Common Stock into a greater number of shares, or (iii) combine or
         reclassify its outstanding shares of Common Stock into a smaller number
         of shares, the Exercise Price in effect at the time of the record date
         for such dividend or distribution or of the effective date of such
         subdivision, combination or reclassification shall be adjusted so that
         it shall equal the price determined by multiplying the Exercise Price
         by a fraction, the denominator of which shall be the number of shares
         of Common Stock outstanding after giving effect to such action, and the
         numerator of which shall be the number of shares of Common Stock
         outstanding immediately prior to such action. Such adjustment shall be
         made successively whenever any event listed above shall occur.

             (2) Whenever the Exercise Price payable upon exercise of each
         Warrant is adjusted pursuant to Subsection (1) above, the number of
         Shares purchasable upon exercise of this Warrant shall simultaneously
         be adjusted by multiplying the number of Shares initially issuable upon
         exercise of this Warrant by the Exercise Price in effect on the date
         hereof and dividing the product so obtained by the Exercise Price, as
         adjusted.

             (3) No adjustment in the Exercise Price shall be required unless
         such adjustment would require an increase or decrease of at least five
         cents ($0.05) in such price; provided, however, that any adjustments
         which by reason of this Subsection (3) are not required to be made
         shall be carried forward and taken into account in any subsequent
         adjustment required to be made hereunder. All calculations under this
         Section (f) shall be made to the nearest cent or to the nearest
         one-hundredth of a share, as the case may be. Anything in this Section
         (f) to the contrary notwithstanding, Thinking Tools shall be entitled,
         but shall not be required, to make such changes in the Exercise Price,
         in addition to those required by this Section (f), as it shall
         determine, in its sole discretion, to be advisable in order that any
         dividend or distribution in shares of Common Stock, or any subdivision,
         reclassification or combination of Common Stock, hereafter made by
         Thinking Tools shall not result in any Federal Income tax liability to
         the holders of Common Stock or securities convertible into Common Stock
         (including Warrants).


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             (4) Whenever the Exercise Price is adjusted, as herein provided,
         the Company shall promptly but no later than 10 days after any request
         for such an adjustment by the Holder, cause a notice setting forth the
         adjusted Exercise Price and adjusted number of Shares issuable upon
         exercise of each Warrant, and, if requested, information describing the
         transactions giving rise to such adjustments, to be mailed to the
         Holders at their last addresses appearing in the Warrant Register, and
         shall cause a certified copy thereof to be mailed to its transfer
         agent, if any. Thinking Tools may retain a firm of independent
         certified public accountants selected by the Board of Directors (who
         may be the regular accountants employed by Thinking Tools) to make any
         computation required by this Section (f), and a certificate signed by
         such firm shall be conclusive evidence of the correctness of such
         adjustment.

             (5) In the event that at any time, as a result of an adjustment
         made pursuant to Subsection (1) above, the Holder of this Warrant
         thereafter shall become entitled to receive any shares of Thinking
         Tools, other than Common Stock, thereafter the number of such other
         shares so receivable upon exercise of this Warrant shall be subject to
         adjustment from time to time in a manner and on terms as nearly
         equivalent as practicable to the provisions with respect to the Common
         Stock contained in Subsections (1) to (3), inclusive above.

         (g) OFFICER'S CERTIFICATE. Whenever the Exercise Price shall be
adjusted as required by the provisions of the foregoing Section, the Company
shall forthwith file in the custody of the Secretary or an Assistant Secretary
at Thinking Tools' principal office and with its stock transfer agent, if any,
an officer's certificate showing the adjusted Exercise Price determined as
herein provided, setting forth in reasonable detail the facts requiring such
adjustment, including a statement of the number of additional shares of Common
Stock, if any, and such other facts as shall be necessary to show the reason for
and the manner of computing such adjustment. Each such officer's certificate
shall be made available at all reasonable times for inspection by the holder or
any holder of a Warrant executed and delivered pursuant to Section (a) and the
Company shall, forthwith after each such adjustment, cause a copy by certified
mail of such certificate to be mailed to the Holder or any such holder.

         (h) NOTICES TO WARRANT HOLDERS. So long as this Warrant shall be
outstanding, (i) if Thinking Tools shall pay any dividend or make any
distribution upon the Common Stock or (ii) if Thinking Tools shall offer to the
holders of Common Stock for subscription or purchase by them any share of any
class or any other rights or (iii) if any capital reorganization of Thinking
Tools, reclassification of the capital stock of Thinking Tools, consolidation or
merger of Thinking Tools with or into another corporation, sale, lease or
transfer of all or substantially all of the property and assets of Thinking
Tools to another corporation, or voluntary or involuntary dissolution,
liquidation or winding up of Thinking Tools shall be effected, then in any such
case, the Company shall cause to be mailed by certified mail to the Holder, at
least fifteen days prior the date specified in (x) or (y) below, as the case may
be, a notice containing a brief description of the proposed action and stating
the date on which (x) a record is to be taken for the purpose of such dividend,
distribution or rights, or (y) such reclassification, reorganization,
consolidation, merger, conveyance, lease, dissolution, liquidation


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or winding up is to take place and the date, if any is to be fixed, as of which
the holders of Common Stock or other securities shall receive cash or other
property deliverable upon such reclassification, reorganization, consolidation,
merger, conveyance, dissolution, liquidation or winding up.

         (i) RECLASSIFICATION, REORGANIZATION OR MERGER. In case of any
reclassification, capital reorganization or other change of outstanding shares
of Common Stock of Thinking Tools, or in case of any consolidation or merger of
Thinking Tools with or into another corporation (other than a merger with a
subsidiary in which merger Thinking Tools is the continuing corporation and
which does not result in any reclassification, capital reorganization or other
change of outstanding shares of Common Stock of the class issuable upon exercise
of this Warrant) or in case of any sale, lease or conveyance to another
corporation of the property of Thinking Tools as an entirety, Thinking Tools
shall, as a condition precedent to such transaction, cause effective provisions
to be made so that the Holder shall have the right thereafter by exercising this
Warrant at any time prior to the expiration of the Warrant, to purchase the kind
and amount of shares of stock and other securities and property receivable upon
such reclassification, capital reorganization and other change, consolidation,
merger, sale or conveyance by a holder of the number of shares of Common Stock
which might have been purchased upon exercise of this Warrant immediately prior
to such reclassification, change, consolidation, merger, sale or conveyance. Any
such provision shall include provision for adjustments which shall be as nearly
equivalent as may be practicable to the adjustments provided for in this
Warrant. The foregoing provisions of this Section (i) shall similarly apply to
successive reclassifications, capital reorganizations and changes of shares of
Common Stock and to successive consolidations, mergers, sales or conveyances. In
the event that in connection with any such capital reorganization or
reclassification, consolidation, merger, sale or conveyance, additional shares
of Common Stock shall be issued in exchange, conversion, substitution or
payment, in whole or in part, for a security of Thinking Tools other than Common
Stock, any such issue shall be treated as an issue of Common Stock covered by
the provisions of Subsection (1) of Section (f) hereof.



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                                         THINKING TOOLS, INC.


                                         By:      ______________________________
                                                  Name:
                                                  Title:
Dated:  ____________, 2000

Attest:


_______________________________
Secretary


                                         STARTFREE.COM, INC.


                                         By:      ______________________________
                                                  Name:
                                                  Title:

Attest:


_______________________________
Secretary


Dated:  ____________, 2000

Attest:


_______________________________
Secretary




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                                  PURCHASE FORM


                                                        Dated ____________, 2000

         The undersigned hereby irrevocably elects to exercise the within
Warrant to the extent of purchasing _______ shares of Common Stock and hereby
makes payment of _______ in payment of the actual exercise price thereof.

                                ----------------

                     INSTRUCTIONS FOR REGISTRATION OF STOCK

Name ________________________________
(Please typewrite or print in block letters)


Address ______________________________


Signature _____________________________





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                                 ASSIGNMENT FORM

         FOR VALUE RECEIVED, ______________ hereby sells, assigns and transfers
unto


Name _____________________________
(Please typewrite or print in block letters)


Address ____________________________

the right to purchase Common Stock represented by this Warrant to the extent of
______ shares as to which such right is exercisable and does hereby irrevocably
constitute and appoint ___________ as attorney, to transfer the same on the
books of Thinking Tools, Inc. with full power of substitution in the premises.

Date ____________, 2000

Signature ___________________