Why not report it to the police? I think is an offence to drive away from an accident and I'm sure they'd chase it up. Also if you reported it to insurance they can make a claim against them too.
Tailgated people, and when they moved out of the way for a turn, he floored it and tailgated someone again. Clearly didn't actually have anywhere to be, as he would never overtake. Just wanted to drive like an idiot for.. fun I guess?
Ran over my foot and called me a pig.