Oh man, how awesome is this? I’ll always be a mouse man for FPS games, but since L4D is such a shared experience, it makes sense to make it as physically involving as possible. This resourceful gamer has hacked a Wiimote input program for XP to pass the sensor data to Left 4 Dead as joystick data. So you can play co-op with a friend right there, screaming and crying as you leave him out there with the horde. You can adjust the sensitivity, shake the controllers for different effects, and I’m sure you could add a few lines in there to config or add functionality in whatever form if you’re code-savvy.
The instructions and code are over at they guy’s blog. He’s also made it work in AudioSurf, which looks fun but a little ridiculous.