The "hey poopyhead' thread made me wonder... Do you have a pet peeve that could be considered incredibly trivial by others? I know I do.
This is car related. I would never leave my trash (coffee cup, food wrapper, shopping bag, newspaper, etc) in a friend's car, or change the heat/air setting or the radio station/volume without asking permission first. Ask first, or better, ask me to make the adjustment(my car, my control). Minor and inconsequential to some/many, but thoroughly rude to me. Sets me off like nothing else...
Oh, and that whole dog poop in my garbage can issue, but that's already well documented.
If you want to come and clean/tidy my house though, I have no control issues there.