I collect pet peeves like some people collect stamps. Here are just a few:
People who intentionally and/or irresponsibly misrepresent facts to make their arguments. See Rush Limbaugh, Michael Moore, and anyone who has criticised the legal justice system based on the McDonald's case.
Queries that begin with a rhetorical question. Or queries that misspell my name, for that matter.
The 4-5-1 formation for soccer, unless you're Barcelona.
Editors who take six months and more to respond to your submission, and then don't have the dignity to apologize. And before you say turnaround is fair play, I always apologize in advance to authors when I've taken a long time in responding to a project.
Small people who use really big umbrellas. You know who you are.