So it turns out some guys made a bundle with some pretty interesting indie games and are selling it under a "Pay what you want" model. They're also giving part of the proceeds to charity too. Info here:

http://www.humblebundle.com/

And if you pay above the average (USD$5.30 as of this writing) you get 2 additional games! So if you were thinking about getting any of the games mentioned here, or even if you just want to try them, it's a darn good offer IMO!

Oh and you get Steam keys for the games you buy, so you can activate them there.