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                                                                    EXHIBIT 10.1
                                  120 DAY NOTE

AMOUNT $200,000                                                     MAY 12, 2003

                  For value received, MicroIslet, Inc., a Nevada corporation,
promises to pay to John J. Hagenbuch, Trustee U/D/T dated September 13, 1995
("Lender") at 353 Sacramento Street, 21st Floor, San Francisco, California
94111, the sum of $200,000, on September 9, 2003; together with interest on the
unpaid principal amount at a fixed annual rate of 4.25%. This note may be repaid
at par at any time prior to maturity in whole or in part in multiples of not
less than $25,000. Accrued interest shall be paid, with respect to any principal
amount prepaid, upon such prepayment, and with respect to the balance, upon
maturity.

                  As additional consideration for making this advance,
MicroIslet, Inc. shall issue Lender a 10-year warrant to purchase 50,000 shares
of MicroIslet, Inc. common stock at a price equal to the closing price of
MicroIslet, Inc. common stock as reported on the OTC Bulletin Board on the day
that the Lender first makes the loan.

                  This Note evidences an advance that Lender made to MicroIslet,
Inc. related to its need for additional working capital.

                  This Note may not be assigned.

                  This Note and all agreements (included the warrant referred to
above) which either are now or which shall become agreements between Lender and
MicroIslet, Inc. are hereby expressly limited so that in no contingency or event
whatever, whether by reason of deferment or advancement of the indebtedness
represented by this Note, acceleration of the maturity date of this Note, or
otherwise, shall the amount paid or agreed to be paid to Lender for the use,
forbearance or detention of the indebtedness evidenced hereby exceed the maximum
amount of interest permissible under applicable law. If at any time, from any
circumstance whatsoever, fulfillment of any provision of this Note or any other
agreement between Lender and MicroIslet, Inc. shall result in or involve
payments or performance which would exceed the maximum legal interest rate,
then, ipso facto, the obligation to be fulfilled shall be reduced so as not to
exceed said maximum legal interest rate.

                           Upon the occurrence of any of the events set forth
below, all principal, interest and any other obligation or amounts due pursuant
to this note (the "Obligations") shall automatically, become immediately due and
payable to the Lender, in each case, without presentment, demand, protest, or
other notice of any kind, all of which are expressly waived by MicroIslet, Inc.:

     MicroIslet, Inc. fails to pay the Obligations when the Obligations become
     due and payable.

     The entry of a decree or order by a court of competent jurisdiction
     adjudging MicroIslet, Inc. a bankrupt or insolvent, or approving as
     properly filed a petition seeking a reorganization arrangement, adjustment,
     or composition of or in respect of MicroIslet, Inc. under the federal
     Bankruptcy Act or any other applicable federal or state law, or appointing
     a receiver, liquidator, assignee, or trustee of MicroIslet, Inc., or any
     substantial part of its property, or ordering the winding up or liquidation
     of its affairs, and the continuance of the decree or order unstayed and in
     effect for a period of 45 consecutive days.

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     The institution by MicroIslet, Inc. of proceedings to be adjudicated a
     bankrupt or insolvent, or the consent by MicroIslet, Inc. to the
     institution of bankruptcy or insolvency proceedings against it, or the
     filing by MicroIslet, Inc. of a petition or answer or consent seeking
     reorganization or relief under the federal Bankruptcy Act or any other
     applicable federal or state law, or the consent by MicroIslet, Inc. to the
     filing of any petition or to the appointment of a receiver, liquidator,
     assignee, or trustee of MicroIslet, Inc., or of any substantial part of its
     property, or the making by MicroIslet, Inc. of an assignment for the
     benefit of creditors, or the admission by MicroIslet, Inc. in writing of
     its inability to pay its debts generally as they become due, or the taking
     of corporate action by MicroIslet, Inc. in furtherance of any of the
     foregoing actions.

                           The principal of and interest on this Note shall be
payable in lawful money of the United States of America in immediately available
funds and without set-off or counterclaim, free and clear of and without
deduction for any present or future taxes, restrictions or conditions of any
nature.

                           MicroIslet, Inc. waives diligence, presentment,
protest and notice of protest, dishonor and nonpayment of this Note, and
expressly agrees that this Note, or any payment under it, may be extended and
any security may be accepted, released or substituted by the Lender from time to
time without in any way affecting the liability of MicroIslet, Inc.

                           If the indebtedness represented hereby or any part
hereof is collected at law or in equity or in bankruptcy, receivership or other
judicial proceeding, or if this Note is placed in the hands of attorneys for
collection after default, MicroIslet, Inc. agrees to pay, in addition to the
principal and interest payable hereon, attorneys' and collection fees incurred
by the Lender.

                           This Note shall be governed by and construed in
accordance with the laws of the State of California applicable to contracts to
be performed wholly within California.

                                       John J. Hagenbuch, Trustee U/D/T dated
                                       September 13, 1995

                                       By:     /s/ John J. Hagenbuch
                                               ---------------------------------
                                               John J. Hagenbuch, Trustee

                                       MicroIslet, Inc., a Nevada corporation

                                       By:     /s/ John F. Steel IV
                                               ---------------------------------
                                               John F. Steel IV, Chief Executive
                                               Officer

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