OK, I wrote a post before and it disappeared or was corrupt so I deleted it.
Anyway, I said: if it's not too cold for skiing it's not too cold for biking
Yes, it's fun. Not everyone can do this or understand but I live near public transportation and I only opt for the subway if it's very cold AND pouring hard at the same time. There is something perversely enjoyable about having your water bottle frozen solid half way through your commute and people at work thinking you're crazy LOL

And, ever since I started riding in cold weather I no longer get sick in Winters. I don't ride to save money, because I actually spend more on my gear, I'm not really trying to save the environment (even though that's a part of it), I'm not completely anti-car (I own one, for weekend gateways) but it's just fun and immensely satisfying, plus it's my main if not the only workout.
Adam