Originally Posted by the beef

Rain bikes usually are set up with fenders, and are bikes that you're not afraid to get dirty or toss around a little.

I live in Seattle, so this is kind of a good idea. I hate cleaning the gunk out of derailleur pulleys and cassettes. Glargh. So my 'rain bike' right now is a steel 1983 Schwinn Super Sport that I converted into a single speed and decked out with a carbon fork. It's 20 lbs, goes fast, and I never, ever have to clean it besides occasionally lubing my chain. Woohoo!