I was driving NB on Clark St in Chicago during evening rush hour which, if you don't know Chicago, is a pretty heavily used road that unfortunately is also frequently only 1 lane in each direction. This asshole in a beat up truck comes along blasting douchey rap and trying to pass people on the right in the parking lane and by jumping red lights. I wasn't having it and wouldn't let him in front of me, so at the next red light he pulled out to my left across the double yellow line, did a quick brake tap to check for incoming traffic, and flat out ran the red light, just so he could pass ONE car and sit with the ass of his truck sticking out into the intersection in the traffic ahead of me.

I was pretty pissed, but halfway down the next block, there was a police car conveniently sitting in a parking spot monitoring the traffic. So when I inched up next to him, I rolled my window down and told him the guy in front of me had been driving like a crazy person and was going to cause an accident. He thanked me for letting him know and pulled the truck over on the spot. Pretty sure from the smell as he passed that the driver wasn't just smoking cigarettes so I'm sure he had a great evening.