My crossover cables are usualy whatever color I made them. I swore off RJ45 connectors years ago, but I still seem to find myself with a crimper every time I need a patch cable. That said, on the comercial side I never noticed any sort of color theme.

At work we've got a couple of the plastic crossover adapters that go on one end of any strait through cable and turn it into a crossover. Of course, these always find homes somewhere permanent when they really shouldn't.

Matthew