At day one of [Reboot](http://reboot.dk) I saw a part of the movie The Mother of all Demos, which was a Doug Engelbart demo of a funky system.
Just take a look at the organ-style keypad to the left of the keyboard in the linked picture above.
When a chord was struck on that *code organ*, notes (or beeps at least) would be heard, and then some command sequence would be emitted on-screen. Ain’t that slick?