Silence of the Sleep is short, but a decent take on the "horror" (I'd call it a thriller more than horror) genre, and from a unique perspective. Definitely worth playing, though. Best game in the bundle in my opinion. Disregard, was thinking of "Among the Sleep." -_-

Universe Sandbox was "alright". For some reason, a lot of people I know loved it (which is why I bought it). It was fun for a couple of hours for me, playing around with planets and building solar systems and such. Nothing earth-shaking, though, imho. The sequel is supposed to be many times better.

Painkiller is a decent run-and-gun shooter, takes place in hell, demons, over the top weapons. Not really my thing, but put together and done pretty well.

The others I don't have enough time in to form a solid opinion. :X

Painkiller is very similar to Serious Sam, only minus the corny humour and plus a lot of gothic brooding. And more gore.