If you're interested in PC digital download sales/deals, check out the site I've been working on:
http://www.cheapshark.com/
Basically it automatically indexes deals from Steam, Amazon, Gamer's Gate, GreenManGaming (and others). It also automatically rates them based on percent off, metacritic score, price history, and a few other factors.
Plus, if you want you can sign up for email alerts that let you know once a game has reached a price you want (or lower).
If you have any feedback, let me know, the site is still fairly new.