I think cold weather cycling is best done when you ease into it, riding in gradually decreasing temperatures. If you've never ridden below 32ºF, don't just jump on the bike when it's 0ºF out, even if you think you're well dressed for it. I'm still learning about how to prepare for winter cycling, and I've been doing it most of my life. I'm always refining my dress. I pay close attention to what part of my body is cold and needs better coverage.

[MENTION=112025]wolfchild[/MENTION] I think cycling presents special challenges, compared with XC skiing and showshoeing. When I cycle, my legs are moving, but the rest of my body is still. I get cold!

[MENTION=381746]mcours2006[/MENTION], you really should try a fixie. It's not for everyone, but it's worth trying. They can keep you warmer than a freewheel bike since your legs are always moving. They can also give improved traction, since you have fine-grained control of your speed. But don't try it tomorrow!