Have purchased more snow melt for the sidewalk in front of the house, but more importantly, collapsible shovel, tread thingie, balaclava, extra-warm gloves, and storage container for the car. Am thinking a little container of gravel might not go amiss either. Car is already stocked with first-aid kit, thermal blankets. The more heavy-duty lost in the wilderness stuff is probably not necessary in urban Chicago, and I'm not planning on driving anyone but me until the snow is cleared again.
My biggest problem during the last snow storm was actually getting my car out of my garage, because I hadn't had a chance to shovel the alley behind it, and the car kept spinning its wheels, etc. I had a collapsible shovel that I used to dig out around the tires, which was fairly miserable, but do-able, and I finally made it out, but then I saw a woman stuck and piteous near her car, and I gave my shovel away to her. So, time to get another.