Winterize your car

Now that you've winterized the house and the kids are busy looking for the cat and wondering where the muffled mewing is coming from you can get down to preparing the car.

Replace your windshield wiper blades. Sure, the ones you have now are fine but you want to keep them that way. The first time you get lazy and try to use the wipers to scrape away the ice instead of doing it by hand you'll ruin them. Put them somewhere safe and steal the blades off of the neighbor's car. Next spring you can put your own blades back on and keep the torn up blades for next winter.

If you've got a checkup coming up go ahead and have it done. Just because the mechanic is less resentful when there aren't clumps of ice and salt falling on him as he tries to change the oil.

Change the oil. The stuff you have now has developed a grudge.

Get the tires inflated. Summer air is bigger than winter air. If you insist on driving on summer air you should have neon lights installed underneath so you don't look odd for riding so low.
Low tires create more friction with the road and lower your gas mileage. And who wants all that surface contact with an icy road? It's much more fun to drive when you're not in control.

Same with the spare tire. If it gets low you know you're just gonna cram more stuff in the trunk and that's just more stuff to have to take out when you're along the side of the highway somewhere.

Get the antifreeze checked. You can pick up a tester at any automotive shop. If you're a bit low you can top it off with any Australian table wine.

Have the brakes checked out. If they're no good make sure the floor is thin enough for you to put your foot through when the breaks fail

Have an emergency winter kit in the trunk. Include blankets or long sleeve coveralls, gloves, and ice scraper, a flashlight, maybe some well preserved nibbles, jumper cables, tow chains, a tool kit, a spare cat, paper towels, a good book, etc. This is so when you get stuck in a snow bank and die you can make the news for dying within a foot of supplies that could have saved you. It could also weigh down the back tires enough to give you more traction.

Make sure there's actual windshield wiper fluid in the car instead of just water. The water will freeze to the windshield and ruin those wiper blades.
Also acceptable is just strapping a cat to the windshield. One blast from the wiper fluid nozzle and the cat will freak out and claw all the ice off.

Keep a bag of kitty litter or sand in the back. It'll provide more weight for traction, you can throw some under the tire for more traction, and you'll need it for the cat you have strapped to the windshield. The cat can also be thrown under the tire for traction.

Check the heater and defroster. Because you know that you're gonna sit there and wait for the ice to melt rather than stand in the cold and chip at it. At least make sure that it can melt the ice quickly.

Get a couple of 9-volt batteries and keep them in the glove compartment. When plugged into each other they put off heat so you can warm your hands. I can't recommend a brand but I know some work better than others.

Have your belts checked and tightened. When they get loose they start to squeal and that's really annoying.

Make sure your 4-wheel drive works. I mean you paid for it so you might as well use it. It's completely worthless on ice, though. Dunno what you were thinking when you bought it.

Check your battery for corrosion. If there's buildup around the terminals pour a Coke on it. Doesn't do you much good but it's cool to watch.

Best of luck.

note: Dougintology is actually a big fan of cats and does in no way advocate driving over them. It is kinda funny to shoot them with wiper fluid, however.