As someone that has had a fit of road rage, I can tell you that day after day of idiots acting like spoiled fucking assholes because they didn't plan to get somewhere on time and will be 3 minutes late because of their poor planning...

After a while, you just feel like letting these assholes know they fucked with you on the wrong day.

My breaking point was at rush hour leaving work, someone trying to fix a flat in front of me (not sure why they didn't pull over, but there really wasn't a place there to do it) and while trying to get him -- and letting him safely have his space and some BWM asshole starts honking. Once I could get around the guy with a flat the BMW tries to get around me, hits me, and nearly sends me into the path of the guy laying on the road.

We all have breaking points...I've gotten extremely angry at assholes honking and riding my bumper when I'm on the right 'slow' lane and doing 5MPH more than the speed limit anyways. People drive dangerously and act like it's your fault. I'm glad my breaking point, however, has only been once someone actually hits me, and almost killing someone else instead. I'm also glad I no longer carry a baseball bat in my car.