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                                                                EXHIBIT 10.57.1

                                SALARY AMENDMENT
                         Dated as of September 1, 2001
                                       To
                              EMPLOYMENT AGREEMENT


WHEREAS, ACTV, INC. ("ACTV") and KEVIN M. LIGA ("Employee") are parties to an
employment agreement (as the same may have been amended prior to the date
hereof, the "Employment Agreement") pursuant to which ACTV or an affiliate of
ACTV currently employs Employee; and

WHEREAS, in a joint effort to address ACTV's current financial needs, ACTV
desires, and Employee has agreed, to amend the Employment Agreement, effective
as of September 1, 2001, to effect a reduction in the annual salary currently
being paid to Employee thereunder;

NOW, THEREFORE, in consideration of the premises, the parties hereby agree as
follows:

1. Salary Reduction. During the period commencing on the date hereof to and
including the earlier of (i) such date (if any) as the Chief Executive Officer
of ACTV may, in his sole discretion, hereafter rescind this instrument for and
on behalf of ACTV by written notice to Employee or (ii) the date (if any) of any
final disposition of all or substantially all of ACTV's stock, businesses and/or
assets (the date of any such rescission or dispo-sition being a "Rescission
Date"), Employee shall accept a $30,000.00 reduction in his current annual
salary, with the result that from and after September 1, 2001 to and inclu-ding
the Rescission Date, Employee's annual salary under his Employment Agreement
(exclusive of any bonus or other compensation payable thereunder) shall,
notwithstand-ing any provision of Employee's Employment Agreement to the
contrary, be Two Hundred Twenty Thousand dollars ($220,000.00), less applicable
withholding taxes and other payroll deductions required by law, payable in
accordance with ACTV's customary payroll practices. Nothing herein shall be
deemed to obligate ACTV (or any ACTV affiliate) to pay to Employee, prior to,
upon or after the Rescission Date (if any), any sum that Employee shall have
foregone prior thereto as a consequence of this instrument, except as herein
otherwise expressly provided in Section 2 below.

2. Severance Adjustment. Any severance that shall become payable to Employee
under his Employment Agreement during or after the term of this instrument shall
be calculated without reference to either this instrument or the salary
reduction effected hereby.

3. Waiver. By his acceptance and execution of this instrument, Employee
acknowledges and confirms his consent hereto and waives any claim that the
herein-specified reduction of his annual salary from the date hereof to and
including the Rescission Date constitutes a breach of, or otherwise provides him
with any right to terminate his employment under, his Employment Agreement.


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4. Ratification. As hereinabove amended, Employee's Employment Agreement is
hereby ratified and confirmed to be in full force and effect.

5. Governing Law. This instrument shall be governed by the laws of the State of
New York, without reference to such State's laws governing conflicts of laws.

IN WITNESS WHEREOF, ACTV and Employee have executed this instrument as of the
date first set forth above.

                                      ACTV, INC.


                                      By: /s/ David Reese
                                          ---------------------------
                                          Title:


                                      /s/ Kevin M. Liga
                                      -------------------------------
                                          KEVIN M. LIGA
                                               ("Employee")