Broke my hand punching the steering wheel because some arsehat once.

And don't get me started on people that sit the middle lane.
And then you have,
White Knights = people that think its their job to police the roads.
Mono speeds = people that do 40 in a 60, and 40 in 30.
Ghost cars = Cars that seem to have no driver or idea of where they are going
Cocks = Used to drive BMW's now drive Audi's, they sit doing 60 in the middle lane and as soon as they see a wankey old Escort van going past they floor so your then stuck in the outside lane. Then they slow down again, and repeat.
And finally, people that don't know that you give way to traffic coming from the right at roundabouts.