The giant Tesla coil at Coachella has always been a hit with fans.
If anybody wants to emulate it (read: rip off the idea) for their own festivals, check out the newest upgrade: a "singing" Tesla coil.
Apparently an electrical expert named Steve Ward recently debuted it at a science fiction and fantasy conference.
He actually "tuned" the noise made by electrical voltage. Search "singing Tesla video" to check it out.