Feel free to add any of your own to this list in the comments and i'll re-post a big list of everyone elses in a week.

Things that Shouldn't Make Me Laugh but that I Laugh at Anyway –

David Schwimmer
Dog attacks
When girls put "Kissing" in their About Me's on Facebook
Women's Basketball
Wheelchairs
Family Circus, the cartoon
Ducks
Cocaine
The end of Million Dollar Baby
Vegans
War Protests
When people are really into Death Cab for Cutie
Anti-Crystal Meth commercials
Drunk people singing Journey
When someone is really really serious about the song they are singing at a Karaoke bar
Hunting shows on OLN
Any sort of erection including my own
Blink 182
If someone loves Chuck Palahniuk
Hot Hot Heat
Poetry readings at an open mic night
The movie Stepmom
When people get worked up and argue politicsĀ 
When drunk indie kids talk about music
Buffalo Bill from Silence of the Lambs