How do you handle EXTREMELY rude strangers?

*Ugh* Today I had to deal with some random rude idiots, and I won't go into detail, but they angered me to the point that I wanted to physically retaliate against them. I hadn't felt that offended in a while, and I was so shocked, that I wanted to skip the cordials and go straight to punching them in the face... So my question is how do you, personally, handle random strangers you don't know who anger you to the point that you want to physically hurt them?... I swear I'm not emo, but sometimes these situations are really frustrate me and make me wonder why some people are allowed to breathe the same air as me.