Engadget has the word of the world’s tiniest NES controller. It’s fully operational, looks the part, and is the size of one of those American “quarters”, however big that is (I seem to remember them being reasonably small, like the NZ 20c piece, which probably means nothing to any of you).

There’s full details on the process involved in building the device over at G4TV, the creators of the device. I like it. You could build one of these into a mouse and play emulated games arcade style games on your PC with some rewiring of the socket.