Ah... Melalvai raises a good point: winter riding. It can be done, save for days when there was a lot of snow or ice on the road. I used a fleece band around my ears and put a cover on my helmet.

Most importantly: good gloves. Below freezing, I use Pearl Izumi lobsters but wonder about the "Icebike Mitts." I also take my bike into my office (or a storage room nearby), since I cannot remove the lock with the gloves and my hands get cold very fast.