> we should ban talking to your passengers on a car too, right

You may be on to something. You've seen the number of people out there who actually turn to face their passengers full on while driving, right?

Actually it's pretty odd. I don't look at the passenger when I'm driving, though of course we'll converse. Even at stop lights, I spend more time checking the light and my rear view mirror than I do looking at my passenger. My responsibility as a driver requires me to do so when I'm driving, whether it's slow, fast or stopped.

This makes a lot of people noticeably uncomfortable.

I've taken to actually turning my face slightly towards people periodically, while keeping eyes ahead -- just to avoid creating a sense of awkwardness.