Not cycling but I was once hooted at aggressively by an Orthodox Jewish guy in a people carrier when indicating to change lanes in Manchester. He barged past and prevented me from changing lanes. I dismissed it as the usual big city rudeness and continued my journey to the station. When I reached the station, there he was, having taken a different route. I couldn't resist saying in the nicest possible way, something like "You ought to learn to relax, if you carry on like that you'll die of a stress-related heart attack!"
Bizarrely he looked at me, smiled and retorted: "Oh I would LOVE that!"
I'm still puzzled by that.