I hate seeing people smoking.
I find it very rude when someones ignores you.
I am sick to death of people who has lots of silly questions.
I think it is incredibly rude to ask users in Internet to do your so much easy homework themselvses.
And the absolute worst is when a person does it many times.
It annoys me when people can't translate "I love playing football" to Russian.
What drives me crazy is when those "people" have not completely understood that I was talking about them...