One of my main irritations is definately public transport. And in particular people sitting in a very busy bus, who insist on sitting on the isle seat, while placing theire bag on the seat by the window. Ofcourse I gesture or ask, always remain civil, that I would like to sit there. Then instead of picking up their bags and shoving their buts to the window seat, they pull up their legs about 3 centimeters and you are expected to climb over them. I hate that!