Wot he said.....
I used to lose it, but now I find that letting have their way then a good punch on a door mirror as filter passed later always makes me feel better. Or, if he's stuck in the traffic, pull up next to him with you visor up and gently tap on the window. When it opens shout
at him and ride off. You will not put yourself at so much of a risk and you really will feel better for it
.