That is pretty cool. I am wondering though, the board is consumable so if they shot in the thing too many times then the bullets may not register. They would just travel through previous shots. I think this would be a TON of fun with airsoft. you could rig up a mechanism for reloading to occur when you actually reload. Then a again you may be able to just put in an unlimited ammo code if one exists. I'm also wondering how the thing interfaces with half life. In all the PC shooters I played the way you aim is to move the entire screen, because your gun points to the center all the time. They shot stuff not in the center of the screen. It would be really cool to use head tracking in combination with this to have the screen display based on where you look.