Would be interested to hear from anyone who has one of these devices installed in their cars:
http://www.ozspy.com.au/products/8-GPS-Tracking/450-Vehicle-Driving-Recorder-System-with-Inbuilt-GPS-Module/
http://spycity.com.au/gs-600driverecorder.aspx
http://www.dod-tec.com/product.php?cat_1st=4&cat_2nd=6

I am thinking of getting one for my car, might be handy if i was involved in a car crash too.

Here is a link to one in action in a truck in OZ
http://www.youtube.com/watch?v=PtHzaeTpYB0&feature=player_embedded