I lifted this off the WND jokes page. Anyone who's a classical music nut (guilty!!) will find this hilarious.
The orchestra was playing Beethoven's 9th Symphony at a concert in the park. They were in the middle movements and the choir didn't have much to do. The basses, in the back, decided to run across the street to get a drink at a pub.
It was a windy day, so they used some string to wrap around their music stands to hold their music in place while they were gone. Once at the pub, they could hear the music and keep up with the progress of the piece.
After a few rounds, they decided to hurry back because the last movement of the symphony was under way. They stumbled back onto the bandstand and were fumbling with the string, trying to get the music loose. Unfortunately, they weren't having much success.
The conductor saw them and instantly figured out what was happening:
It was the bottom of the ninth, the score was tied and the basses were loaded.