Season 3's cafeteria spinner. In the second subround, a huge lump of tomato sauce caused all five contestants on the spinner to wipe out at once! (Complete with super-super-slow-mo replay of the sauce being thrown out.)
In another episode, they happen to mention aliens... then the whole contest briefly falls into sheer insanity.
"Ragin' Cajun" William Davis Jr. must simply be seen to be believed. Most of his qualifier round run was spent yelling at the course (or just yelling).
When he wins, he opens his jacket, yells and thanks President Obama.
The "Hotties vs. Nerds" episode has the Total Carnage course, where once the game started, nearly four-fifths of the contestants got knocked out by the first arm.
Hell, the whole "Hotties vs. Nerds" episode is one hilarious moment after the other.
Follow up "Hotties vs. Nerds v2" doesn't disappoint either.
Once "Couples" episode featured two hilarious moments involving a giant airbag- one contestant is thrown through the air, doing a cartwheel in the process... and another is thrown into the air and apparently doesn't come down until after the commercial break!
The tribute to "Real Men of Genius"-based tribute to the inventors of their obstacles:
Here's to you, Crazy Obstacle Inventor Guy! (Mr. Crazy Obstacle Inventor Guy!) Others have made 25 foot slides, but only you would point it straight into a giant spinning snowflake. (Oh god, my knee just touched my forehead!) No sane person would build a pneumatic penguin that throws people into a 900 gallon vat of eggs. Because that's straight-up crazypants! But for you, that's just another day at the office. (Don't forget the salmon!) Only a mind like yours could look at an innocent platform next to the big balls and say, "Hey! I bet that would make a great slingshot for human beings!" (Using people as projectiles!) Go ahead and take a bow, o king of the qualifier! You've made your mark by making other people fall down. (Mr. Crazy Obstacle Inventor Guuuyyyy!)
Heck, almost anytime a contestant fails a part of the obstacle course and falls into the liquid. Especially when it involves the Big Balls.
There was one contestant (who was nicknamed 'scarecrow' after playing one in a stage version of The Wizard of Oz) who got hit TWICE by the crankshaft in one wipeout, the first time lifted him up by the neck only to dump him groin-first onto the second area of it that was rising up. Jill immediately says "Best wipeout ever!"