Tomorrow, you can try out Left 4 Dead
on your PC free for 24 hours
. It will contain the new Survival Mode as well so you get the latest version of the game to test out. Really, you should have this game already and if not, don't let this opportunity slip you by the try one of the best games of last year for free. You can even start pre-loading it right now so that you're ready to go for Friday.