Anyone here heard of Natural Selection 2? It's a sequel to a Half-Life 2mod, but unlike the original mod which requires a Source game to play, NS2 is stand-alone and runs on it's own engine. I don't typically play FPS games for PC much anymore, but this game reminds me of AvP and the gameplay looks like a lot of fun.

correction it is a sequel to a Half-life 1 mod, it never had to anything to do with Half-life 2.

http://en.wikipedia.org/wiki/Natural_Selection_(video_game)

NS2 is running on the spark engine, which was built from the ground up, which itself is amazing of what they have been able to do with it.

http://en.wikipedia.org/wiki/Natural_Selection_2

It's a fine game. It'll only get better once people get more familiar with it and start working as a team. Not that it's just monkeys running solo right now though. I'm actually surprised how many people do what the Commander tells them to do like repairing stuff and so on. 
 
Mod support is gonna be sick as well. There's already some cool mods from the beta.