Wayne Coyne of the Flaming Lips has himself a double neck with a bit of a difference. One neck is standard guitar neck, the other is a Guitar Hero button panel with Koas Pad for strumming.
Here's an explanation for it from Coyne:
“I've constructed this great looking Guitar Hero double-necked guitar thing here because there's a lot of kids out there that think this is actually how you play guitar now — that you just press a series of four or five buttons and and sort of different sort of sequences and it makes every sound that the guitar can make,” says Coyne. “So when you do this stuff, you know (strums actual guitar on the first neck), it's not as impressive as hitting the right green and red combinations.”
See it in action here (2 minutes in).
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