What is the funniest thing that has happened either at a rehearsal, concert, or contest. For us, we were recently doing a concert, about half way through the second half, our first bass had a solo, the piece was called "Bass in the Ballroom", if any one knows it. Near the end the bass has a solo bit where a bit of improvisation can be done, but he really threw us by stopping, picking up his music, looking puzzled at it, then turned it upside down, put it back on the stand and then launched off into "Those Magnificent Men in Their Flying Machines" accompanied by our second man down cornet. It totally threw the rest of us and our MD but the audience loved it. He and second had conspired in secret for the event. Wonderful stuff.