http://www.mastercard.com/us/specialoffers/savings_discounts/

Discounts available at Alamo, BLOCKBUSTER, Crutchfield, eBags, Midas, JC Penny, etc.

http://usa.visa.com/personal/discounts/index.jsp

examples: 20% off at ebags.com, $15 off $75 at sharperimage, $10 off $55 at ACEhardware, $5 off $40 at etoys.com and more.