Looking at the Ouya controller and the Wii U Pro controller, it seems like videogame inputs are reaching convergence. But some games will still be defined by their unique interfaces.
Punch the Custard takes usual videogame inputs and surrounds them in custard. Brandon Boyer at Venus Patrol explains:
Created by George ‘v21‘ Buckenham, the creator of Cubes, A Bastard and co-creator of the Proteus Frog God Mod, the game functions via a simple Arduino controller that completes a circuit when a player stands with one hand on a sheet of tin foil and the other is used to, well, you know, punch the custard — the mixture’s dilatant properties (I did indeed have to wikipedia that) firming the fluid as you strike it.
The more you punch, the harder it gets, and the game also asks you to stop punching at times, so you'll keep watching it.