I'm kinda like Zeus too (I shutter at the thought but it's true). I have a 1-3 hour commute each way depending on traffic so I've gotten in the tendancy to 'veg out' while driving. I'm very aware of my surroundings but do not pay attention to other drivers.

Recently I was giving a co-worker a ride home (he ownes a jacked F-350). He started giving me the riot act because I didn't respond to another driver who was giving me the thumbs up. I've tried paying more attention but it's just not in my nature.