PriceProtectr is designed to save you money with stores, who refund you for price drop within 30 to 60 dyas.
Simply buy a product from Amazon, Best Buy, Circuit City, Costco, Future Shop, Office Max, Target, or any other supported chain of stores, copy and paste the URL of your product, provide your email and PriceProtectr will keep an eye on the price of the items that you bought. If the price goes down within the price protection period you will receive an email and could contact the retailer to refund you the difference.
So far PriceGrabr is protecting 3569 items and have saved $59,367.00 to its customers. This is a cool service and I suspect that it might become quite popular.