People who suddenly stop in the middle of the footpath or a doorway or in a shopping centre with f-all consideration for the fact they are in a busy location with a million other people around them. If you need to stop, move the fuck out of the way!! Had a whole group of people (of a particular race that seem to have a particular habit of not giving a f about other people around them - I'm sure you can guess) yesterday right in the middle of one of the main entrances to Myer in the CBD. 8 of the knobs and NOT ONE thought to simply step to the side!