It's a "reward" program of a different sort, but I like eBates. You get a % added to your account for shopping through their site (varies by store--I've gotten anywhere from 2% to 10% of my purchase, but I've seen ones listed up to 25%). And they only send out a check every 3 months (if you have more than $5 in your account--otherwise it rolls over to the next 3 month period), so you have to wait until they send it. But it is "cold, hard cash!" My first check was for over $18. Now I've got over $22 for my second check, and still shopping!
I've also been doing surveys for MySurvey and have about $30 in points racked up, but I may just let that one sit for a while longer before cashing in. It takes a while since most of the surveys are worth about 10 points (or $0.10). But, hey, a dime for 2 minutes of my time? Sure.