Binary Domain, Ryu Ga Gotoku Studio’s 3rd person robot shooter, is free on Steam as part of Make War Not Love 3 campaign!
It also comes with Streets of Rage 2, and Condemned: Criminal Origins. All you need to do to get your code is head over here and click Redeem prize.
You’ll need to enter a valid email address and it could take 24 hours for the code to be sent to you; but hey free is free!