I've had that happen to me a few times. I don't know really what to do or say about it, it's about the most stupid thing someone can do on the road, and i agree with your way of dealing with offenders
but it's really hard to react to such behaviour appropreately.
Another thing that happend to me - you may not believe this, but i give you my word it happened - was, i was driving in the street where i live (30kph limit, but since it's a narrow street with cobbled with stone you would normally find on the pavement, lot's of people think it's a traffic-reducing zone (the speed limit for those would be 7kph, or thereabout). Anyways, this women stopped me by jumping in front of the bike, i had to brake fairly hard to come to a halt in time because i was doing about 60. She then shouted at me as if i was a rapist, and finally called the police, i stayed calm, when she finished the call i asked her what she's going to tell the police, she said something along the lines of "that you drove like a maniac". I said "you didnt measure my speed, did you? and the police won't be able to anything, youre going to get into trouble and i live three houses down, if you need me, just drop by", and i drove away. I never heard from her again (it was last summer) so she must've called them off.
Ten minutes after the incident i felt really good about it, for some reason...
(i just want to say that i don't have any points on my license and was never cought speeding, never caused or even was involved in an accident, i think i'm a fairly good driver, and the road was completely empty, it was late in the evening, i recognise that i shouldn't have driven so fast, but thinking back to it, i'm fairly confident the situation was quite safe)