Probably already mentioned but windscreen wipers...
- They squeak or screech even slightly
- They don't remove every drop of water or leave streaks (will pull over immediately to correct this)
- They are on more than they need to be (eg: set to constant when it's just spitting. This only annoys me when I'm a passenger as I don't ever do it. It even annoys me when other cars that driving past do it lol)
- When people forget to turn them off after it stops raining (are you paying attention to your surroundings if you don't notice two black sticks swinging in front of your face?)
- Small wipers that don't wipe enough of the window
Yeah, windscreen wipers...
- When people park their car and don't bother to park their wipers
- wipers that go "click" when they reverse direction
- any blade that is more than 6 months old
- any "universal" blade
- the fact that even with a massive discount a genuine set of BMW floppy blades is over $80
- the fact that genuine BMW blades are so bloody good I am willing to pay over $80 for them every 6 months