I thought I'd do a little bit about winter cycling. Basically, I'd have to say that it all comes down to this: it's not as hard as you think.
A good jacket helps a lot. I have this one. Add a fleece layer underneath and it's all I need for the coldest weather we get here in Chicago. A fleece hood is helpful too and maybe a pair of rain pants. I wear boots most of the winter anyway, so I don't wear special foot gear except for the very snowiest of weather.
What's more important than the gear is just deciding to do it.
There is a bit of an art when it comes to riding in the actual snow, but it comes with practice. I made it through this past winter and missed biking to work only twice because of the weather, which is to say when it was an ice storm. And there was one time I refused to go grocery shopping because it was so freaking cold, so we got the I Go car.
If you wanted to start winter cycling, you wouldn't have to be as hard core. You could decide to cycle on days when there is no snow on the roads, when it's not too cold. We have a surprising number of days in the winter here in Chicago where it's above freezing and there's no snow.
Why would someone want to do this? What is it that keeps me on the bike, year after year? Firstly, there's nothing quite so amazing as riding through an inch or two of powdery snow on streets that haven't been plowed, nor rutted up by cars, maybe with a few soft flakes still falling. There's the feeling of independence a bike gives, which for me, a car never did. But what I love most able winter cycling is the simplicity of it. I just get on the bike and go.