I recently found myself driving behind a champagne-colored mini van after it swooped dangerously in front of my car without warning as we both exited the freeway in heavy traffic. (Based solely on the description of that vehicle, could you make an educated guess about the demographics of the driver?)
As it turned out, we were both taking the same 'back way' to avoid the rush hour crawl. So I ended up following this mini van through a winding series of residential side streets as it 'rolled' through several stop signs, perpetually drove well over the speed limit, sometimes veered into oncoming traffic, and never once signaled before turning.
Then about a mile or so later this same mini van, which had been more-or-less careening down the street, suddenly came to a complete stop at a stop sign and dutifully signaled for a right hand turn before continuing. It then made a slow right turn with almost military precision and drove at exactly the speed limit for a block before pulling slowly and deliberately into a local First Baptist Church.