Make sure to keep your windshield washer fluid filled.
and make sure it's winter grade fluid (rated for freezing temps)!
I once had summer stuff in there (doesn't smell as bad because no anti-freeze) and as soon as I turned the wiper spray on the whole window froze over and I couldn't see shit while I was driving.
scary shit!
good advice! I didn't even think about the whole system freezing.
and if you're going a place that cold also get a (fresh) heavy duty battery. ours had trouble starting the car when it was -35F also in Montreal