Valve has finally released the public demo for Left 4 Dead, the highly anticipated co-op zombie shooter. Fire up your Xbox 360 (or Steam on your PC) and cracking on this! The demo’s only going to be available for a week or so, till the game hits stores.

In it, you’ll play through two levels that do a good job of showing what a frantic, insane time the game is. You really have to rely on your teammates, or you’ll quickly die… whether it’s from a horde of zombies or one of the super-beasts, such as the smoker, who shoots out a long tounge to grab you from across the room. Here’s a tip- have fun with the pipe bombs. When you throw them out the zombies will swarm it as it gets ready to explode, and the red mist that follows is incredibly satisfying.

While you’re waiting for the demo to download (and trust me, you’re going to want to play this one) check out the first 15 minutes of gameplay footage coutresy of G4 below. You’re going to want to get in on this action.