Chasing the Cup
There's this one that I watch over and over and over again. The one where they chase the guy in the plastic cup suit all throughout the episode. He jumps in the water and uses his straw as a way to breathe, and then in the end, when they call a truce, they beat him with their nightsticks just as a joke to see how tough his costume is. And then, as they're all laughing and becoming friends, etc. he gets hit by a truck. I don't know why it's my favorite, but I crack up every single time.
Oh and the best part is at the end...when he runs. Great stuff.