Most epic fail in anime? I'm going to have to say Takami Akai saying that 2ch was like sniffing an anus (even though he may be right). He should have expected a shitstorm after saying that. Also, one of the staffers of Gainax condemning otaku to death. Not a good idea, guys.
Extremely hard to top School days but I'll give it a shot.
How about Satou failing at trying to commit suicide multiple times throughout Welcome to the NHK?
LOL! Wlcome to the NHK was funny but c'mon a bullet to the brain is the correct way to suicide....fuckin pansy....the talkin appliances was a trip though >.>