Having to repeat myself.
Left-lane pokers. Especially when you get that rolling roadblock kind of situation where the dude in the right lane is poking and the dude in the left lane is poking at just about the same under-the-speed-limit speed.
On the subject of DC drivers, fucking RUBBERNECKERS. No, somebody getting a ticket or a minor fender-bender is not so goddamned interesting that you have to screw up the whole side of the Beltway by slowing down to take a look. Are your lives really that bloody dull?!? And you, Virginians with your head up your cell phone, HANG THE FUCK UP AND DRIVE.
And the irritation to end all irritations, people who think that if something didn't happen to them, it must also not have happened to you and therefore you're making it up. Or the corollary, if something isn't valued by them, it also shouldn't be valued by you. Example: "I was in pain once but I willed it to go away/prayed it away, so therefore you should be able to do that too". I don't know why it comes as such a shocker to people that we're not all exactly the same with exactly the same needs, interests, and body chemistry. You: still not the center of the universe.