DRM-free PC game titles are up to 90 percent off, but stock is limited on all included titles.
If you're looking for DRM-free PC games on the cheap, and you have some time to browse this afternoon, GOG.com is running its probably-now-annual Spring Insomnia Sale.
Here's the rundown: GOG.com puts a game up for sale (as of me typing this sentence, it's Seven Kingdoms: Ancient Adversaries). The title is marked down significantly (in this case, 75% off $5.99, down to $1.50). Each deal is good on a limited number of copies, and once they're gone, the process repeats on a different title.
There's no set end time on the sale -- it goes until all included games are sold, down to the very last copy.
I just bought FlatOut 2 for two bucks -- 80 percent off the normal $9.99 price. If you feel the need for some cheap PC goodness, now's the time to get it!