When I was in 3rd grade or so, my friends and I were obsessed with this one particular poop joke about a canary, who was flushed down the toilet for some reason or another, and started singing "Riding down the river on a chocolate bar!" (Can anyone help me out here?) Sophomore year of college, my roommate Susan posted a Dave Barry column about taking a shit on the back of our bathroom door, so visitors could read it and chuckle in the crapper. Just these past two weeks, my buddies and I chose "Diarrhea Anne Frank" and "Weak flow, incomplete emptying" as our Quizzo team names. Classy.
There's a lot of people my age who like to pretend that making poop jokes is beneath them, that they are too sophisticated and mature to laugh at such juvenile topics. While I understand their need for intelligent humor (for every episode of South Park I watch, I try to balance it out with something more intelligent...like Futurama) I also feel like: everyone poops. (see above.) You can either acknowledge this fact, and laugh about it, or walk around crapping out your mouth (à la South Park) because your head is shoved so far up your ass, you can't tell where the bullshit ends and the truth begins.
As for me, words like pooped, nincompoop, poop deck, and party pooper will ALWAYS make me laugh, and I'll even go so far as to make up my own phrases, such as as "poopcorn chicken," "pooperazzi," "Sir Poop-a-Lot," and "Poopsylvania." Call me immature -- I say, Poop on you!