Day 7: Favorite Free RPG
To be fair, I haven't gotten to really play this yet. That said, the people behind it at Posthuman Studios are old friends of mine. I've edited various bits of the line over the years, and so I know first hand just how good a job they do. It's released under Creative Commons; the book retails for $50, with the PDF for $20, but as it is a CC release, you can get it for free online and then choose to pay later.
This book is in its 4th printing now, with a full and robust set of supplements building out the universe and investigating what it means to live in a world where identity is decoupled from physicality. I admire this work greatly, and I suggest that if you haven't yet taking a look at this for some reason, you really should.