I had a co-worker who's ringtone was his 5 year old daughter repeatedly saying "Dad, someone's on the phone, Dad, someone's on the phone..." over and over again...
A co-worker has a ring tone that keeps repeating "BLAH, BLAH, BLAH, BLAH..." in a very loud voice. It's a little funny the first two or three times you hear it but gets old very fast.
At a climactic, breath-holding denouement of a play i was attending, someone's phone started ringing, and their ringtone was a recording of someone shouting "Angel! Pick up the phone! Angel! Pick up the phone!"