Driving Pet Peeves. What really ticks you off?

[Landau Stable]

As per the title, what really gets to you the most?

To begin, i'll mention one of mine: I can't stand it when i am towing with my car trailer, and someone pulls out in front of me forcing me on the brakes. They take off, leaving me to struggle up to speed again. (usually, there is no one behind me, so it wouldn't have hurt them to wait)
Even worse when it comes to stopping, and they pull out in front of me at the last second, reducing my braking distance at an intersection etc

And now i hand it over to the good folk of the forum........