At a music camp there was a very extroverted, 'look-at-me' type pianist playing the Chopin Polonaise in A major (Op 40. No 1). At the end of the trills in the 'trio' section, he smacked his head on the lid of the front board of the grand piano after an excessive body movement to hit the Ds.The only thing that would have made it funnier would have been if his action had hit the lid and it closed on his fingers! During the camp, we'd ask him how he got the red bump on his forehead...