It's electric! (boogie woogie woogie)
Okay, this is pretty cool:
These guys have rigged up two midi controlled Tesla coils. They generate large sparks (feet long, by the looks of it) that necessarily produce "thunder", and they modulate the current so that the thunder produces a tone. Then they can just input music via a midi interface and it plays the music just as if it were a set of speakers. There's also a video of them playing the Imperial March from Star Wars using a dude in chain mail as an electrode.
Clearly, future performances should include he Highlander soundtrack (preferably using a sword as an electrode) and using playing a theremin through the device.