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                                                                Exhibit 10.15

                                  cMeRun Corp.

                       Nonqualified Stock Option Agreement

      THIS STOCK OPTION AGREEMENT between cMeRun Corp., a Delaware corporation
(the "Company"), and ________________ (the "Grantee") dated as of
___________________ (the "Grant Date").

      For good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto act and agree as follows:

Section 1. The Plan

      This Agreement is subject in every respect to the terms of the Company's
2000 Equity Incentive Plan, as amended to date (the "Plan"), a copy of which is
attached hereto as Exhibit A and is incorporated herein in its entirety by this
reference. Capitalized terms used herein and not otherwise defined shall have
the meanings ascribed to them in the Plan.

Section 2. Grant of Option

      The Company hereby grants to the Grantee, as of the Grant Date, an option
(the "Option") to purchase up to _________ shares of Common Stock of the Company
(the "Option Shares") at a price per share of $____,both the price and the
number of shares being subject to adjustment only as provided in the Plan. This
option is not intended to qualify as an incentive stock option within the
meaning of Section 422 of the Internal Revenue Code of 1986, as amended, or any
successor provision thereto (the "Code").

Section 3. Terms of Option

      Subject to such further limitations as are provided herein, the Option
shall be exercisable following the date hereof in three (3) installments, with
the Grantee having the right hereunder to purchase from the Company the
following number of Option Shares upon exercise of the Option, on and after the
following dates, in cumulative fashion:

            (i) on and after _____________, up to _____________ of the total
number of Option Shares;

            (ii) on and after ________________,up to an additional
__________________ of the total number of Option Shares; and

            (iii) on and after __________________, the remaining Option Shares.


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Section 4. Option Term

      The Option, to the extent it has not been exercised or sooner terminated,
shall expire on the close of business on the day that is ten (10) years from the
Grant Date (the "Option Term").

Section 5. Cessation of Grantee's Employment

      (a) If the Grantee ceases to be employed by or retained as a consultant to
the Company or one of its subsidiaries (the "CMER Companies") by reason of the
Grantee's death during the Option Term, the Option shall be exercisable, to the
extent the Option was exercisable on the date of the Grantee's death, either by
the Grantee's executor or administrator or, if not so exercised, by the legatees
or distributees of the Grantee's estate, only during the twelve (12) months
immediately following the Grantee's death, after which time the Option shall
terminate.

      (b) The treatment of the Option upon cessation of the Grantee's employment
for any reason other than death shall be as set forth in the Employment
Agreement between the Grantee and the Company dated _____________ (the
"Employment Agreement"), it being the intent of the parties that if there is any
conflict between the terms of this Stock Option Agreement and the Employment
Agreement, the terms of the Employment Agreement shall govern.

Section 6. Exercise of Option

      (a) The Grantee may exercise the Option with respect to all or any part of
the number of Option Shares then exercisable hereunder by giving written notice
of election to the Company at One Cabot Road, Hudson, MA 01749, Attention:
Corporate Secretary. Such notice shall specify the number of Option Shares as to
which the Option is to be exercised.

      (b) At the time the Option is exercised, the Grantee shall make full
payment for the Option Shares purchased, in cash or by certified or bank check
or, to the extent permitted by the Board of Directors (the "Board") or any
committee appointed by the Board to administer the Plan, by delivery of shares
of Common Stock of the Company, valued at their Fair Market Value (as defined
under the Plan) on the date of delivery, or pursuant to a cashless exercise
program adopted by the Company. The Grantee shall pay to the Company or make
provision satisfactory to the Company for the payment of any taxes required by
law to be withheld by the Company at the time of the exercise of the Option or
the sale of the Option Shares acquired upon such exercise.

      (c) In the event exercise of the Option otherwise would require the
Company to issue a fractional share of Common Stock of the Company, except as
otherwise provided below, such fraction shall be disregarded and the purchase
price payable in connection with such exercise shall be appropriately reduced.
Any such fractional share shall be carried forward and added to any shares
covered by future exercise(s) of the Option. Notwithstanding the foregoing, if
the Grantee (or any of the individuals named in Section 5(a) above in the event
of the Grantee's death) is exercising the Option in full (including with respect
to any fractional share) in


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connection with the cessation of the Grantee's employment or consulting
relationship with the CMER Companies pursuant to Sections 5(a) or 5(b) above,
then, in lieu of any fractional share that otherwise would be issuable to the
Grantee, the Company shall deliver to the Grantee upon exercise of the Option a
check representing the fraction multiplied by the Fair Market Value of one share
of Common Stock.

      (d) Notwithstanding anything to the contrary contained herein, the Option
shall not be exercisable unless either (a) a registration statement under the
Securities Act of 1933, as amended, with respect to the offer and sale of the
Option Shares by the Company shall have become, and continues to be, effective,
or (b) the Company determines in its sole discretion that an exemption from
registration under said Act is available with respect to the offer and sale of
the Option Shares by the Company. If deemed necessary by the Company, the
certificate representing the Option Shares may be endorsed with a restrictive
legend.

Section 7. No Rights of a Shareholder

      Neither the Grantee nor any personal representative shall be, or shall
have any of the rights and privileges of, a shareholder of the Company with
respect to any Option Shares, in whole or in part, prior to the date of exercise
of the Option.

Section 8. Nontransferability of Option

      During the Grantee's lifetime, the Option shall be exercisable only by the
Grantee and shall not be transferable other than by will or the laws of descent
and distribution without prior approval of the Board.

Section 9. Employment Not Affected

      Neither the granting of the Option nor its exercise shall be construed as
granting to the Grantee any right with respect to his or her continued
employment by the Company. Except as may otherwise be limited by a written
agreement between the Company and the Grantee, the right of the Company to
terminate at will the Grantee's employment or consulting arrangement at any time
(whether by dismissal, discharge, retirement or otherwise) is specifically
reserved by the Company.

Section 10. Governing Law

      The validity, construction, interpretation and effect of this instrument
shall be governed by and determined in accordance with the law of the State of
Delaware, without regard to conflicts of law principles.

Section 11. Amendment of Option

      The Option may be amended or modified at any time by the Company;
provided, however, that the Grantee s consent to any such amendment or
modification shall be required


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unless the Board of Directors or Compensation Committee (if any) of the Company
determines that the amendment or modification, taking into account any related
action, would not materially and adversely affect the Grantee.

Section 12. Notice

      (a) Any notices required or permitted hereunder shall be addressed to the
Company at One Cabot Road, Hudson, Massachusetts 01749, Attention: Corporate
Secretary, or to the Grantee at the most current address of the Grantee
appearing in the records of the Company, as the case may be.

      (b) Either party to this Agreement may, by notice to the other given in
the manner provided in Section 12(a), change the designated address for future
notice.

                                   *    *    *


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IN WITNESS WHEREOF, the Company has caused this Agreement to be duly executed by
its officer thereunder duly authorized and the Grantee has hereunto set his or
her hand all as of the _____ day of_______________ 2000.

                                       C ME RUN CORP


                                       By
                                         Its

      The foregoing Option is hereby accepted on the terms and conditions set
forth herein and is expressly subject to all the provisions set forth in the
Company's 2000 Equity Incentive Plan, a copy of which is attached hereto as
Exhibit A.


                                            _______________________, Grantee


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