One of my co-workers took a kid's watch (on the hour it would play a little tune, and say it is now four o'clock, five o'clock etc) and hid it in one of the partitions. The watch was about 5 hours off, and REALLY annoying. At 2:20 it would say "the time is now 6:00".

The problem was, you could only hear the watch for about 10 seconds and then it was in oblivion. It took us about 3 weeks to find that stupid thing, and it was a good laugh afterwards.

GRRRRrrrr!