There's a nice thread on the Musician's Corner page on the Genesis Forum about embarrassing onstage moments. This one made me laugh: (courtesy of iamreal):
'I was playing a gig in Holland many years ago. As a sort of show-thing at the end of the last number I would sometimes get up from the drumkit and throw the sticks at it for the last beat. (well it was the seventies.) Anyway, this time I lost my balance and fell against the back of the stage. There happened to be a fire door which opened as I fell against it and the next moment I was OUTSIDE! How I didn't break my neck I don't know. It was about a four foot drop so I couldnt get back in so I went around to the front entrance. There, they wouldn't let me in. Kept saying "band finished, closed". In the end the other band members came looking for me and I got back in!'