I didn't see this posted anywhere, but the December Games w/Gold are Gears of War and Shoot Many Robots. If you haven't already beaten Gears, pick it up now and play it. Just do it. Say hi to Dom and Marcus for me. It's available for free through December 15th. On December 16th, Shoot Many Robots will be available. Check the link above. It looks like a stress reliever!
Enjoy!
Enjoy!