This website has some pictures of a guitar constructed entirely out of LEGO pieces.
The guitar was actually playable, but the ‘truss rod’ for the back was not sturdy enough to handle the string tension for long which is why there are no strings in the pics.
Approximately 100,000 LEGO pieces were used to build this instrument. Four colours: black, red, tan, and white. Looks awesome!
Does anybody know of some more?