Live Performances Gone Awry

I couldn't help but think about the time I saw Steven Tyler stagger across the stage and pass out back in the early 80's, and how Stevie Nicks cancelled a concert at the New York State Fair around 1987-88 because she had such a bad cocaine problem. The Stevie Nick's show really upset me because she didn't reschedule and they didn't announce it until two hours before the show.

Anyone one else have any poor experiences at a live show they'd like to share? Grateful Dead welcome but please no stories of fans.