This idea came to me when I was thinking about how a first person shooter would be different if every player was paper thin. It would be interesting to see how a multiplayer shooter would play if you could only see or shoot someone if they were facing roughly the same direction as you. For instance, if a player was running perpindicular do you, it would be nearly impossible to hit him.
If I ever get around to making this game I would want to style all of the characters, weapons, and levels in a paper theme. Each player could be an origami person and weapons could be things like a gun that shoot scissors or a staple gun. I think that a paper theme has a lot potential.