Not as bad as getting shot of course, but in 1982 I saw The Who in concert, and a relatively newcomer at the time, John Cougar (before the Mellencamp came and went), opened for them. While he was on stage, mid song, somebody from the crowd (huge, this at ASU football stadium in Tempe, AZ), threw a bottle at him and hit him in the head. He fell over, blood running down his face, and after a few choice words, was taken back stage and had to be stitched up extensively. He was hit pretty hard. He came back out 20 minutes later, all bandaged up, and finished the concert.