I think it'll work at champs/footaction. I remember somebody said he could use his birthday coupon at champs in this thread.
print/save it to your phone just in case...
http://niketalk.com/t/146443/current-coupon-codes-requests-or-s-warning/1920#post_16146106
http://slickdeals.net/f/5064484-American-Express-20-Statement-Credit-with-100-Purchase-at-footlocker-Twitter-facebook-foursquare-Account-Required
American Express: $20 Statement Credit with $100 Purchase at footlocker
Expires 8/31