DriveThruRPG has a deal where you donate $20, all of which goes to Doctors Without Borders for Haiti relief, and get 179 books/supplements in PDF form. I'm sure most of it is shovelware, but there are enough gems to make it well worth while if you're into roleplaying at all.
(I'm linking to this blog post rather than RPGNow directly, because this post has the complete list of titles, whereas RPGNow's list craps out midway through the "C"s.)