The closest to making me laugh in this thread was the vent thing but I KEPT A STRAIGHT FACE. (It was so, so hard though. But I made it through.)
Runner up would be Human Tetris, butHuman tetris can't make me laugh anymore maybe because when I was in Japan last year visiting Chie (This was before we were married) I watched the crap out of that show. Here are my submissions for funniest dualogy ever. These make me laugh my a*** off.
[ame]http://www.youtube.com/watch?v=OHxyZaZlaOs[/ame]
[ame]http://www.youtube.com/watch?v=h8yHguvYYyQ[/ame]