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                                                                  Exhibit 10.1
                                                              ------------------

                               CITY NATIONAL BANK
                       633 West Fifth Street, Tenth Floor
                          Los Angeles, California 90071
                    PHONE (213) 615-8349 FAX (213) 615-8339

S. Steve Tsoflias                                            Downtown Commercial
Vice President                                               Banking Center


                               January 28, 2002

Mr. Gerald L. Salzman
Daily Journal Corporation
915 E. 1st Street
Los Angeles, CA 90012

     Re:   Revolving Note dated January 2, 2001, in the Original Principal Sum
           of $4,000,000.00 ("Note") executed by Daily Journal Corporation and
           Sustain Technologies (collectively "Borrower") in favor of City
           National Bank ("CNB")

Dear Mr. Salzman:

     This letter supercedes the letter dated April 11, 2001. Capitalized terms
not defined in this letter have the meanings given them in the Note. This letter
is hereby incorporated into the Note (this letter and the Note, collectively,
the "Note").

                        A. ADDITIONAL EVENTS OF DEFAULT.

     The following shall constitute additional Events of Default under the Note:

1.   Failure of Borrower to furnish CNB, within the times specified, the
following statements:

     1.1   Within forty-five (45) days after the end of each quarterly
           accounting period of each fiscal year, a financial statement
           consisting of not less than a balance sheet, income statement, and
           statement of cash flows, with notes thereto, prepared in accordance
           with generally accepted accounting principles consistently applied,
           which financial statement may be internally prepared;

     1.2   Within ninety (90) days after the close of each fiscal year, a copy
           of the annual audit report for such year for Borrower and the
           Subsidiaries including therein a balance sheet, income statement,
           reconciliation of net worth and statement of cash flows, with notes
           thereto, the balance sheet, income statement and statement of cash
           flows to be audited by a certified public accountant acceptable to
           CNB, and certified by such accountants to have been prepared in
           accordance with generally accepted accounting principles consistently
           applied.

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     1.3   Within thirty (30) days after the end of each month, excluding months
           that coincide with the quarter ending or fiscal year ending, a
           financial statement consisting of not less than a balance sheet and
           income statement, prepared in accordance with generally accepted
           accounting principals consistently applied, which financial
           statements may be internally prepared;

     1.4   Such additional information, reports and/or statements as CNB may,
           from time to time, reasonably request;

2.   Declare or pay cash dividends and repurchase company stock in aggregate in
     excess of $600,000 during any fiscal period, without CNB consent;

3.   Make acquisitions in excess of $500,000 during any fiscal period without
     consent from CNB;

4.   Change the majority of the existing Board of Directors, except through
     merger or sale of the Borrower so long as the buyer is a stronger credit
     and is approved by CNB in its sole discretion.


                      C. ADDITIONAL TERMS AND CONDITIONS.

     The following additional terms and conditions shall also apply to the Note:

     1.  Environmental Indemnification.  In consideration of CNB extending
credit to Borrower, Borrower has agreed to indemnify CNB against any claims that
may arise as a result of Borrower's business activities that are environmental
in nature and for which CNB may be named as a liable party.

     Borrower agrees that it shall indemnify and hold harmless CNB, its parent
company, subsidiaries and all of their respective directors, officers,
employees, agents, successors, attorneys, and assigns from and against any loss,
damage, cost, expense, or liability directly or indirectly arising out of or
attributable to the use, generation, manufacture, production, storage, release,
threatened release, discharge, disposal, or presence of a hazardous substance
on, under, or about Borrower's property or operations or property leased to
Borrower, including but not limited to attorneys' fees (including the reasonable
estimate of the allocated cost of in-house counsel and staff). For these
purposes, the term "Hazardous substances" means any substance which is or
becomes designated as "hazardous" or "toxic" under any Federal, state, or local
law. This indemnity shall survive repayment of Borrower's obligations to CNB.
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         Except for documents and instruments specifically referenced herein or
in the Note, this letter and the Note constitute the entire agreement of the
parties hereto and supersedes any prior or contemporaneous oral or written
agreements, understandings, representations, warranties and negotiations, if
any, which are merged into this letter and the Note. If you agree to accept the
terms of this letter, please sign this letter, and return them to me on or
before February 15, 2002.

Sincerely,

City National Bank, a national
banking association,

By: /s/ S. Steve Tsoflias, VP
    ------------------------------------------
    S. Steve Tsoflias, Vice President

Accepted and Agreed this 1st day of
February, 2002

Daily Journal Corporation

By: /s/ Gerald L. Salzman
    ------------------------------------------
    Gerald L. Salzman
Title: President


Sustain Technologies, Inc.

By: /s/ Gerald L. Salzman
    ------------------------------------------
    Gerald L. Salzman
Title: Secretary