http://www.gog.com/If you didn't already know, this has been going on for the last few days and continues to the 25th, I believe.
-TONS of games on sale for the next week.
-Many more on DEEP discounts for a few hours at a time, if you watch the website. Up to 90% off.
-Mount & Blade for Free for 48 Hours (sorry guys, you already missed this one, but I started a thread on it when it was valid)
-Witcher 2 Free With "Stamp Collection". Visit the site for 7 days, and collect 7 stamps, and you get this plus a movie for free.
-The Gamers: Director's Cut for Free (see the line above for details)
They really outdid themselves this year!