Good snow brush and shovel, avoid any brush with plastic joints as those break when you need them most.They also sell traction mat that goes under the tire but I've never tried any.
You only came here in the summer! Ice is the big killer here. Driving home from work last year I stopped almost half a dozen times in less than 5 miles to help push people's cars to get them moving. It's made worse by the fact that this city is mostly hills, and the salt means that the ice is almost always wet. I've even slid quite a ways in my Jeep, which is why I'm seriously looking at some studded tires this year.And, in true Multitool.org fashion, the hatchet I keep in the Jeep is an Ontario Knives SPAX! Def