Mary writes, regarding yellow cars: I know a man who is colorblind, and yellow is the only color he can distinguish as different when he looks at a lot full of cars.  Thus, his trucks, cars, and motorcycles are all the same taxi-shade of yellow. One less mystery in the universe, no?

That seems like a perfectly reasonable yellow car justification. I can only hope for the sake of taste and decency everywhere that all these butt-ugly cab-looking things I keep seeing have sensible, colorblind owners - particularly the Bug that likes to get parked in front of my driveway. I have yet to see an all-out yellow motorcycle, although there was that Vespa a couple weeks ago.