I finally bought a bike specifically for commuting this year. During the good weather I would ride my Trek 5200 Triathlon bike into work, and ride my mountain bike in the bad weather. I had put studs on the mountain bike, (Cannondale Rush) but the snow and road salt was killing it.
I bought a Surly 1X1 on Craig's list for $300, and have to admit it has become my favorite bike to ride into work. There are very few moving parts, so even with the snow and road salt there is very little maintence. I think that even when the weather turns for the better I am still going to use this bike for my year round cummuter.

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