You remember the Bing Cashback program, right? It handed out cash rebates for stuff you purchased via the Bing portal. So, for example, if you were going to buy something like the 50-inch LG 50PK540 plasma HDTV from TigerDirect for $799.99 (a mighty nice deal today, by the way), you might get back 10 percent of the purchase price--just by clicking through Bing before placing your order.
Alas, Microsoft pulled the plug on Bing Cashback last June--but the concept lives on. In fact, before you buy another thing, head to CashReporter.com. The site aggregates rebate info from various cash-back sites to show you who's offering the biggest refund for any given store.
All you do is search for the e-tailer you want (or browse the store categories), then click on the cash-back site with the highest rebate. (If you're not already signed up with that particular site, you'll have to do so before proceeding.)
CashReporter has listings for hundreds of online stores--though you won't find a cash-back offer for each and every one. From what I can tell, the site pairs with only about a dozen cash-back services, and the list doesn't include my new favorite: FatWallet Cash Back. Some of the best rebate deals I've found were from there. In fact, I daresay you should start your search there, then head to CashReporter to see if there's anything better.
Update: I was informed by both companies that FatWallet has been restored to CashReporter's listings (apparently it was taken down temporarily due to a site redesign).
Keep in mind that whatever cash-back service you use, it can take 90 days or more to get your rebate. But if you buy a lot of stuff online (and if you're a regular around here, I know you do), it's almost crazy not to use a site like FatWallet to save a few bucks. The rebates may be just a few percentage points here and there, but they do add up! (If you've had any experience with these cash-back services, pro or con, hit the comments and spill your guts.)
And speaking of adding up, I continue to be a big fan of Swag Bucks, which awards you points in exchange for watching videos, playing games, searching the Web, participating in polls, and so on. The more points you collect, the bigger the prize you can claim.