I'm a big fan of wishlists and planned purchases, and websites that track prices of your wishlisted items and notify you when there are deals are thus something I find highly useful. I'll share a few that I use but I am looking for more recommendations. Browser addons or just any software that does the same welcome too. Let me start:
IsThereAnyDeal - Gamers will love this one. Import or start wishlists from a variety of online stores and get notified when there is a sale that meets your criteria. Also tracks interesting vouches and bundles. I've got it set to email me when there are 75% off deals.
eReaderIQ - Big fan of ereader books because I don't need space to store them. This website again lets you import or set up wishlists and get notification emails based on your criteria. It's simply tied to your email so you don't need a separate account with password.
I also use the browser addons
InvisibleHand and
Honey, the former which does price comparison while you look at a supported online store, where as the latter will try and find coupons for you.
So, which ones do you use and would recommend?