HAWKEN: Hey Day9, for one of the Fridays you do another game

It's F2P beta at the moment, and I have had an enjoyable amount of fun on it :D

http://www.playhawken.com/

It has decent graphics, dowloads pretty quickly, and there are a couple of game modes right now. It is a "mech" fps but to me at least it would sympathize with your TF2 experience ;) It isn't as insta kill as a lot of other FPS titles (even going to put TF2 in there) and it can make for a very entertaining daily ;) Plus, you will have fun I am sure ;)