This subject came up at work, and I thought I'd introduce it on the Affect.
What's the funniest scene you've ever watched in a movie. To kickstart the topic, I'll offer some of my favorites in no particular order:
Blazing Saddles... welcoming in the new sheriff. "We extend a laurel and hardy handshake to our new...nigger."
Something About Mary...Ben Stiller fighting with the dog.
Happy Gilmore...Happy and Bob Barker fighting on the golf course in a Pro/Am.
Airplane...A line forming to slap a woman who has gone into hysterics.
Caddyshack...Danny and Ty discussing lumberyards, college and life while Danny caddies.