You might consider this one :
http://www.tirerack.com/tires/tires....+240+Sottozero
Pirelli Sottozero, I saw this tyre at work last year at the Nurburgring, IN the snow (imagine driving 20.8 km flat out on a race track coverd in snow !!!) by a test driver on a BMW 540 i.
That guy went faster on the snow then the average driver on that same dry track !
It's not to promote fast driving, or harakiri speeds, but it shows how capable that tyre is.
Anything you want to be good at your car, it has to be the tyres, especially in the winter...