Portal 2

Portal 2 drops anytime between now and Tuesday morning. I say anytime between them as Valve has given its fans a chance to play a bunch of indie games that they are promoting (and in turn the indie games had a hand in promoting Portal 2) to help unlock an earlier release time on Steam.

Current time release countdown as well as games that still need playtime can be found here:
http://www.aperturescience.com/glados@home/

Further information can be found on Reddit

In their anticipation a good friend of mine baked a Portal cake for her son. I think she had fantastic results. I only regret that I was not able to partake of the cake myself. Full Image here