It's like the Humble Indie Bundle, so yeah, it's pay what you want, but if you want the steam keys you need to pay at least 0.01BTC.

Since I can't post in the Off-Topic category, I'll post it here and hope someone moves it.
https://www.thebitcoinbundle.com/
A bundle of four indie games (Spirit, World of Goo, Eufloria, And Yet It Moves,  +music of all four games), for Linux, Mac and Windows, that can be bought only with bitcoins!!!