I live in Victoria, which is the Schwalbe North American headquarters. They have just come out with a new winter tire that looks ideal for black ice, frozen bridges etc. It's called the Marathon Winter. Here is a picture of the tread:


Here is a link to the write-up:
http://www.schwalbe.de/gbl/en/homepa...f55a26c5f00189

They look ideal for occasional ice. I commute on Schwalbe Marathon Plus and Marathon Supreme today and am very happy.

The bad news is $70/tire and a total North American inventory of 70 pairs (well, 69 now I guess).