I put a set of 700x35 Nokian W106 on my fixed. First thing I noticed, these tires are heavy! ~2 lbs each. The set weighs >2.5 lbs. more than my other set (700x28 bontrager race lite hardcase). I had to gear down to spin these tires comfortably. So be warned...

Awesome on ice and compacted snow, couldn't have (quickly and safely) biked to work this past week without them...