1. Herds of joggers running against traffic in the bike lanes
2. Cyclist who think they have pedestrian rights
3. The electric busses tethered to overhead power lines that try to pass
4. Drivers who think it's funny to yell
5. Roadie pacelines who don't announce their passing
6. Cars that do the rolling stop at 4 way stop sign intersections
7. Drivers who think bikes belong on sidewalks
Edit: Adding some more:
8. People who leave trash in my basket/rack
9. Drunk people who sit on my locked bike and pretend they are on a motorcycle