Hey folks-
thanks for the great ideas! The lizard skin fork cover and the pipe insulation (+1 for creativity) both sound like good possibilities. I live in san diego, but, judging from some quick googling, the bike racks here seem pretty standard. I think it's partly that my bike configuration is a little uncommon: wide road fork (to accommodate aggressive cyclocross tires) and no rim brake. On any bike with a rim brake (road, canti, whatever), the rack arm will not dig into the fork because the brake is in the way. And most road forks are much narrower anyway, so the arm might actually reach around.
I basically agree with the comments on getting around on a utilitarian bike, but since I only have one *nice* bike, I really love to ride it all I can. It's a steel cyclocross bike, so it's really not far off a commuter, the main impractical aspects being that it's 1) a bit flashy looking, so not something I want to leave locked up and 2) the carbon fork, which has been replaced with an inexpensive steel fork (
Kona project 2, which I think could survive a nuclear blast). I have a 17 miles commute to work, or a 5 mile ride + bus ride, so I usually take the bus in, and then do the ride home. Given the length of the ride (plus the nice trails around work that I like to ride sometimes), it's really nice to have the cross bike with me.
xenologer: actually the scratch is fairly deep. Think of a flat head screwdriver being pressed into the fork with the stops and starts of a rickety bus.. Carbon is fairly strong stuff, but can't handle any sort of lacerations. Frankly I'm as surprised as anyone that full carbon bikes are becoming more common for cyclocross and mountain bikes..