Okay, here is my biggest pet peeve EVER:
(Hopefully I haven't started out another post with that same opening - if I have, disregard because this time I'm serious.)
An ambulance is coming from behind, so like a dutiful citizen you pull over to let it pass. It does, and then the *sshole who's pulled over behind you cuts in front of you to get back on the road just as you're trying (like everyone is trying) to get back on the road. You stupid turd, wait your turn! We ALL had to pull over, and now we're ALL getting back on the road. Don't try to get ahead in a situation where people are carrying on with their lives after taking a moment to pause and do the right thing. WAIT! Life has turns, and you should wait yours whenever possible.