What about a file that, whenever you played an applicable video game, you were made to believe that, while you are, say moving around with the keyboard, think you are in the game, moving around and etc.
Like, if you played a FPS like quake, you would think think you are running around with a gun in hand and etc.
Or playing a flying game, you think you are flying around in the cockpit.
I think this would be awesome, imagine the experiance playing half-life!