Green man gaming are giving away a game free to celebrate their birthday.
The offer code is FREEGIFT
Now this offer had been posted previously but is now showing as expired so I assume that they got some more keys.
The game I got was Three Ded Zed http://store.steampowered.com/app/291390/Three_Dead_Zed/
Wilsh88 says that the games available are
Three Dead Zed
Corporate Lifestyle Simulator