In general, but not exact, order of increasing irrational annoyance:
--The expression "my bad"
--The overuse of "like" as filler. I don't have any specific anal-retentive reason for disliking its use in moderation by a native American English speaker, but god damn, sometimes people like use it such like that like they sound like they're like having a like stereotyped like Tourette's episode, or some sort of weird like grammatical seizure. This might seem like a reasonable pet peeve, but the anger it engenders is totally out of proportion to the offense.
--People who can't handle spicy food. Buck up you pussies.
--People who refuse to try something I recommend because it "sounds nasty" or "looks nasty"
--People who ridicule the learning of some specific language because of a lack of immigrants that speak it. There's something called literature you retarded fucks.
--Spanglish. I mean, come on, *fuck*.
--Love poetry
That's about all I really run into on a regular basis. The rest of my irrationalities are mostly my modest set of unusual phobias.