The worst I ever had was when I was into motorized bicycles. I had a 1940's Colson 24" cruiser, beefed up china motor, and it would do 50+mph. Not your average tweak bike.
Was riding on Newport Blvd toward the beach, keeping up with most of the traffic, and stopped at a light. A guy behind me in a piece of shit 80s American car was pissed when the light turned green and I didn't suddenly rocket off the line like a motorcycle, so he rode two feet off my fender, honking and yelling shit at me.
When he got a chance to pass me, he swerved into my lane and pretty much tried to take me out, but there was enough shoulder for me to get out of the way, but then he kept brake checking me.
As this was going on, two "real" bikers, bearded, burley guys on custom chops came up from behind us, rode up alongside the asshole in the car, and shouted all kinds of shit at him, menacing him, and pretty much forced him off at the next exit.
They didn't follow him, but gave me some thumbs up and rode away.
Shit like that makes my day... (edited)