In the dorm, one of the favorite intramural sports was water fights: dousing and bombarding one another with water from squirt guns, glasses, balloons, even wastebaskets. Since each room had a sink, there was endless ammunition. The most frequent target was the resident assistant.
Approaching his room one afternoon, the resident assistant noticed his door was ajar. Looking up, he saw a pail of water balanced on the door's edge, ready to fall on him. As he took down the pail and emptied it into his sink, he thought: Those crazy guys actually thought they could fool me with that old gag!
But then he noticed that "those crazy guys" had removed the drainpipe beneath his sink.