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EXHIBIT 23.1
INDEPENDENT AUDITORS' CONSENT
We consent to incorporation by reference in this Registration Statement of
eSpeed, Inc. on Form S-3 relating to eSpeed, Inc. Non-Qualified Employee Stock
Purchase Plan of our report dated March 24, 2000, appearing in the Annual Report
on Form 10-K of eSpeed, Inc. for the period ended December 31, 1999, and to the
reference to us under the heading "Experts" in the Prospectus, which is part of
this Registration Statement.
/s/ Deloitte & Touche LLP
New York, New York
December 19, 2000
