Tesla Coils do more then just look cool shooting up electrical arcs in mad scientist's laboratories. The Austin, TX based science society known as The Geek Group can actually get them to play music. As this video demonstrates, output from two towering Teslas have been modulated from a control unit in order to generate the tones you hear. All that means is you get a light show and sounds from the same instrument. The buzzy music is kinda what you'd expect from a giant electrical gadget.
The Geek Group: Super Mario Theme
More Tesla music from another group of enthusiasts:
Steve Ward: video
Steve Ward: music
Now if only these guys would get together and jam with the 1-bit and tape-record folks...