The bike commuters here at GOOD are a spoiled bunch weather-wise. While much of the country shivers, we're basking in seventy degree winter weather. We applaud you two wheeled commuters braving the single digits.
We found this Streetsfilms cold weather pedal pushing primer quite helpful. From proper clothing layering and headgear—balaclava anyone?—to full fenders and frequent chain oiling—these Chicago toughs have you covered.
Got more winterizing tips? Share them in the comments below.
Copenhagenisers will hate it ("OH NOES, LYCRA") but if you're a realist commuting outside of the bike friendly parts of the world during winter, this has some nice links for you.
As for me, I cut my commute down, and travel by Brompton. As it's only 7 miles a day, "normal" clothing is the order of the day - I increase the number of pairs of socks I wear according to how cold it is. I also highly recommend sport specific gloves - in my case, specific for horse riding, as my warmest are a pair of Sealskinz equestrian gloves.