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                                                                   EXHIBIT 10.37
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                            SECURED PROMISSORY NOTE

$10,000,000.00                                   Los Angeles, California

                                                 January 31, 2000

     FOR VALUE RECEIVED, the undersigned (Borrower) promises to pay to the order
of GREYROCK CAPITAL, a division of Banc of America Commercial Finance
Corporation (Greyrock), at 10880 Wilshire Blvd. Suite 1850, Los Angeles, CA
90024, or at such other address as the holder of this Note shall direct, the
principal sum of $10,000,000.00, payable in the amount of $833,333.34 principal
per month, plus interest as hereinafter provided, commencing on January 31,
2001, and continuing on the last day of each succeeding month, until the earlier
of the following dates (the Final Payment Date): (i) January 31, 2002, or (ii)
the date the Loan and Security Agreement between Borrower and Greyrock dated
January 31, 2000 (the Loan Agreement) terminates by its terms or is terminated
by either party in accordance with its terms. On the Maturity Date the entire
remaining unpaid principal balance of this Note, plus any and all accrued and
unpaid interest, shall be due and payable. Notwithstanding the foregoing, if the
Additional Capital (as defined in the Schedule to the Loan Agreement) is not
received by Borrower on or before January 31, 2001, then the entire remaining
unpaid principal balance of this Note, plus any and all accrued and unpaid
interest, shall be due and payable in full on January 31, 2001.

     This Note shall bear interest on the unpaid principal balance hereof from
time to time outstanding at a rate equal to the following: The interest rate in
effect throughout each calendar month during the term of this Note shall be the
highest Prime Rate in effect during such month, plus 2.0% per annum, provided
that the interest rate in effect in each month shall not be less than 8.0% per
annum. Interest shall be calculated on the basis of a 360-day year for the
actual number of days elapsed. Prime Rate has the meaning set forth in the Loan
Agreement.

     Accrued interest on this Note shall be payable monthly, in addition to the
principal payments provided above, commencing on January 31, 2000, and
continuing on the last day of each succeeding month. Any accrued interest not
paid when due shall bear interest at the same rate as the principal hereunder.

     Principal of and interest on this Note shall be payable in lawful money of
the United States of America. If a payment hereunder becomes due and payable on
a Saturday, Sunday or legal holiday, the due date thereof shall be extended to
the next succeeding business day, and interest shall be payable thereon during
such extension.

     In the event any payment of principal or interest on this Note is not paid
in full when due, or if any other default or event of default occurs hereunder,
under the Loan Agreement or under any other present or future instrument,
document, or agreement between Borrower and Greyrock (collectively, Events of
Default), Greyrock may, at its option, at any time thereafter, declare the
entire unpaid principal balance of this Note plus all accrued interest to be
immediately due and payable, without notice or demand. The acceptance of any
installment of principal or interest by Greyrock after the time when it becomes
due, as herein specified, shall not be held to establish a custom, or to waive
any rights of Greyrock to enforce payment when due of any further installments
or any other rights, nor shall any failure or delay to exercise any rights be
held to waive the same.

     All payments hereunder are to be applied first to costs and fees referred
to hereunder, second to the payment of accrued interest and the remaining
balance to the payment of principal. Any principal prepayment hereunder shall be
applied against principal payments in the inverse order of maturity.

     Borrower agrees to pay all reasonable costs and expenses (including without
limitation reasonable attorney's fees) incurred by Greyrock in connection with
or related to this Note, or its enforcement, whether or not suit be brought.
Borrower hereby waives presentment, demand for payment, notice of dishonor,
notice of

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nonpayment, protest, notice of protest, and any and all other notices and
demands in connection with the delivery, acceptance, performance, default, or
enforcement of this Note, and Borrower hereby waives the benefits of any statute
of limitations with respect to any action to enforce, or otherwise related to,
this Note.

     This Note is secured by the Loan Agreement and all other present and future
security agreements between Borrower and Greyrock. Nothing herein shall be
deemed to limit any of the terms or provisions of the Loan Agreement or any
other present or future document, instrument or agreement, between Borrower and
Greyrock, and all of Greyrock's rights and remedies hereunder and thereunder are
cumulative.

     In the event any one or more of the provisions of this Note shall for any
reason be held to be invalid, illegal or unenforceable, the same shall not
affect any other provision of this Note and the remaining provisions of this
Note shall remain in full force and effect.

     No waiver or modification of any of the terms or provisions of this Note
shall be valid or binding unless set forth in a writing signed by a duly
authorized officer of Greyrock, and then only to the extent therein specifically
set forth. If more than one person executes this Note, their obligations
hereunder shall be joint and several.

GREYROCK AND BORROWER EACH HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY ACTION
OR PROCEEDING BASED UPON, ARISING OUT OF, OR IN ANY WAY RELATING TO: (I) THIS
NOTE; OR (II) ANY OTHER PRESENT OR FUTURE INSTRUMENT OR AGREEMENT BETWEEN
GREYROCK AND BORROWER; OR (III) ANY CONDUCT, ACTS OR OMISSIONS OF GREYROCK OR
BORROWER OR ANY OF THEIR DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, ATTORNEYS OR
ANY OTHER PERSONS AFFILIATED WITH GREYROCK OR BORROWER; IN EACH OF THE FOREGOING
CASES, WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

     This Note is payable in, and shall be governed by the laws of, the State of
California.

                                        PETOPIA.COM, INC.

                                        By /s/ GREGORY SMITH
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                                        By ___________________________


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