A few years back a friend replaced his battered old Jeep with a shiny new model. Almost immediately he noticed that on the road he got a lot less respect. Folks were generally careful about getting too near to his old disreputable-looking vehicle, but apparently felt no such qualms about cutting off a shiny new Jeep.
As I have discovered, if you drive a minivan you get even less respect. It took a few months (I don't do a lot of driving in traffic if I can help it), but finally it sunk in. For some reason other drivers feel not the slightest qualm at doing rude things (even somewhat dangerous) around a minivan.
The road cretins (most often sporting a baseball cap and driving a small pickup) are usually quite easy to predict. While I like to drive a bit faster than most other folks, at the same time I prefer to keep a safe distance between my car and the car ahead. This gap proves incredibly alluring to road-cretins, who have no qualms about cutting in (often without signalling) and slowing down - far too close for my comfort.
Once I figured out what was happening, I could change the game. While the minivan is no road-rocket, with a 200hp engine it scats reasonably well. When I could predict the next moves of an impatient/impolite driver would include diving into the space in front of my car, the gap would mysteriously dimish just enough, and then widen when other traffic blocked access to that space.
I'm thinking of adding a flaming death's-head to the front, and an "I brake for hallucinations" sticker to the rear. Just enough to penetrate the mental haze of the less mentally active drivers, and make them think twice (or even once) before doing something rude :).