As someone who bikes everywhere, I think this is the most annoying thing I encounter.

[gratuitous]

9. A lot of competition for "most" annoying

But it's surely very annoying. On my daily commute, I ride a multi-use path to cross a very busy street, four lanes and a left turn median. There's a crossing light, which pedestrians and cyclists can activate with a button. I cross this street twice a day every day, nearly 500 times a year. I always wait for the light, even those mornings when traffic is light to non-existent. I can't tell you how many times a motorist has STOPPED for the green light to wave me across four lanes (which may or may not be occupied by other motorists who may or may not stop). I've waved the knuckleheads through every time, sometimes quite animatedly. I've seen two rear-end collisions because someone stopped for a green light, and a lot of close calls.

Motorists: Don't stop at a green light. Please.