This is a really easy way to find sale items on Amazon, but works for many others. Simply search google with the following terms:
"you save" "(PERCENT%) PRODUCT RETAILER
"you save" "(60%)" wallet amazon
Increasing the percentage from 10 to 80 only takes about 20 seconds and works quite well, especially for sites that don't use Google Product (which often misses these).This is quite a simple trick and works on numerous retailers, play.com for example uses the same percentage format to promote deals, for instance:
"you save" "(50%)" helicopter play
Ebuyer is slightly different where an amount has to be entered. Two deals above will get you a cheap wallet or helicopter too :-).