I have a dash cam. Am thinking about getting one facing the rear. They have some units that already have a front/rear pair of cameras on them.
It's the way of the Future.
B4 I got kicked to the curb for being old (no real problem as I now get do the skiing in Mont. everyday the lifts are open that the rest of America doesn't want to do), I was working on collision avoidance systems that included vision as an input.
Reviewing the video data collected during development driving convinced me that it would be a Good Thing TM to have on a personal vehicle.