At the last improv session...
One joke got quite a laugh from the team. We were playing "It Just Gets Worse", where four players take turns to tell the story of a disaster which has befallen a small town, each taking on a different persona.
The disaster was, "The post van has broken down". The story got to the point where an angry naked man who wanted his Super Duper Food Processor was chasing a titanium-legged feral boy through a forest with a phlegmatic postman hot on his heels...
"If you're a naked man running through a forest, and only a postman can see you - do you make a sound?"
It's one of those "You Had To Be There" things. But it was hugely satisfying.