[0]: http://www.thetruthaboutguns.com/2011/01/brad-kozak/the-mass...
Say you installed a media player. Now you'll have to convince a jury that you didn't install a media player just so you could watch videos while driving, and therefore were distracted at the time.
I had a SatNav where an "unable to detect park gear" warning always showed up (I had a stick shift, so it the wires were connected to the hand-break). The guy at the shop couldn't figure out why it was shorting so he just disabled it and said, "Don't watch DVDs while driving."
You know I never did use the DVD player in there ever, not even while parked, in the 5 years I had it.
NB: I have almost no idea how liability and insurance works in the US.