here's mine, definitely an urban bike, for Montreal all weather duty.
The frame was a good find - 20$ for a 1982 Velo Sport mountain bike, back when mountain bikes were basically 26" touring bikes. It has burly dropouts, and an extended wheelbase for panier use. I've found that in the winter panniers are not ideal, they get caught by the sidewinds too much, so I use my messenger bag.
It's built with good, practical parts, and is soon to be converted to threadless with a Surly Long Haul Trucker fork.
It has a pre 1 1/8" headset, slightly larger than 1", but for a 1" fork. ("BMX" style headset) I'll have to convert it with loose ball bearings.

In the winter so far it's done very well. The wide tires are good to soak up bumps, and it grips in snow and ice. The geometry is weird (54cm seat tube, 60cm top tube...) but I've found a way to fit it to me properly. In the summer I run Marathon 26x1.75's.





Haven't had any problems yet, but I can see why people chose to ride fixed gears in places with harsh weather. So much less maintenance. Speed modulation could be done through the gear, reducing the constant sandy, salty, gritty wear on your rims.