Haven't seen it mentioned, but you can (should) also throw some salt bags (or whatever, sand leaks so I would prefer water softener salt) into the back for some added weight on the rear tires.
But the first step to any winter driving in the Z should be winter tires. You could get away with all-seasons, but if you drive your car anywhere at all like a sports car during the summer, you'll probably get more value out of dedicated snow (and cold temp) tires that you take off for the warmer months. Wear out your summer tires on their own, and keep the winter ones for several seasons.
The one thing that I miss from other automatic shiftable vehicles is the ability to start from a stop in gear 2 rather than 1. Manual guys have no problems, of course.
Thankfully, even with the smallest amount of forward motion you can move right up into 2nd.
Me, I have my old car around for use in the winter.