What is your biggest pet peeve about winter drivers?

Mine is people who don’t clean the snow off their cars completely. First there are the people who just clean off a part of driver’s side window and hunch over the steering wheel, peering out, and look like they’re driving an igloo with a porthole in it. That’s just annoying. Second, there are the people who clean everything but the roof of their car. That is both annoying and dangerous; if, when you’re following behind them on the interstate at 55+ mph, the whole thing comes flying off the roof in one big chunk. I’ve never had one hit me, I try not to follow that closely, but one time a chunk of roof snow was launched off the top some nitwit’s car, at just the right speed and trajectory, that it came more than close enough to scare the living bejeezus out of me. Man, I was furious. No, road rage though, don’t worry.