Here's a funny story about when Pink Floyd was recording Wish You Were Here - so there in the middle of recording, in the studio, when in walks this hobo, with a crazy beard and long hair. Pink Floyd is all looking at each other, when Nick Mason, the keyboardist, says "Hey - that's Syd!".
He was so burnt out and drug addled that no one recognized him. He's still alive, and there was a picture of him in a recent guitar magazine, taking out the garbage or something.
see you on the dark side of the moon