http://www.bicycletimesmag.com/conte...raction-system

Chains on car and truck tires have been widely accepted for decades in colder climates, so why not bikes? Turns out, no one has made it work - until now. SlipNot uses braided steel cables and galvanized steel chain links to keep you moving in the snow. They come in two widths and are avaialbe for 26 and 29-inch tires. Retail price is $85 a pair. After a less-than-awesome experience with studded tires last winter, there's a good chance you'll be seeing more of these in the pages of Bicycle Times.