People who don't engage their brains

It doesn't matter what people are oblivious to, if they aren't doing anything that should take their focus, then they should be aware of their surroundings.

For example, people who walk slowly, having a conversation, side by side on a narrow sidewalk or hallway. Especially when they don't move to a side when other people are coming from in front of them. Behind is more excusable, you can't see that, but in front? Good God, have some decency.

Also people who ask questions, while sitting at or near a computer, where the answer to the question can be found from a quick search. Things like "how do you spell x?" I don't know, you're the one with the machine that has spell check in front of you, why don't *you* figure it out?

Basically it drives me crazy if people don't think just a little bit and notice stuff around them.