We played an outdoor show once and someone tossed a dead raccoon up on stage. Our singer/guitar player wasn't impressed at all and walked off stage. I was confused by both the raccoon and our early departure. We were headlining that one, too. Weird.
Another time, after our set, some heavily tattoo'd punk rock dude liked my drumming enough to toss me his watch. It seemed like a really sincere gesture, even though it was a Rolex knock-off that probably never worked. I guess it's the thought that counts.