What makes you angry?

I've decided that stupid people make me angrier than almost anything. I'm talking about the kind of stupid that they shoulda known better, or they're too lazy to think. People whose view of the world is no wider than the distance from the couch to the TV. People who don't take the time or effort to imagine anything outside themselves and their petty concerns. This is a willful kind of stupid I'm talking about, not the kind of uneducated stupidity that can be cured by, well, education. The really pernicious stupidity is the the kind that shuts its eyes and ears and doesn't see and doesn't listen. There's nothing in particular that has ticked me off; I'm just thinking in the abstract right now. And I just felt like being angry about something. Mostly though I'm in a great mood.