I once had some really freaky front grille-less painted-over-logo mini-van glued to my Boxster's butt for over 10 miles on two highways before a stupendous act of evasive driving (IMHO

) on my part.
I was driving with courtesy the whole time - going about the speed of traffic, using my blinkers, etc. All of a sudden this van pulls up so close I can't see his bumper. Sped up, too many people in front of me, he caught up. Slowed down and moved out of the high speed lane, he stayed right behind. Slow, continued variations on these ad nauseum for several miles... finally came the time to move to the secondary highway on my route and he started to follow, so I gave it a bit o' throttle on the ramp - thought one of his tires were going to blow, based on the sound, but the idiot kept coming fast.
OK, no way am I going to let this guy follow me to where I'm actually going to stop.
Finally found a point where I could put on the sting... watched for a point where I was coming up on an exit and had two car lengths free on the left, put on the left blinker, started left (as does he) and then I ducked right into the single car length open on that side. Now I'm behind him and take my next exit... and he's stuck for several more miles. Loop around and take the back roads to my appointment.
That guy was psycho, the worst of the experiences so far. Usually folks are nice (sometimes get the "what type of car is that?" or more often kids yelling out what appears to be the standard kid phrase "NICE CAR!" - usually in unison from the backseat of a SUV

) but sometimes if I just simply pass someone they seem to go postal (and I'm not a weaver). In most cases, if I simply slow down they lose interest... but not that death van guy...