my office is at work and i dont see the need to have a computer or tablet in my car.
do you guys work out of your car? if so, then i suppose it *could* make sense...but since HU's provide most of the entertainment and email/voice from my smartphone, i see less and less of a reason why one would need a computer in a car.
if i had to compose something on my computer, i'd stop the car, hop to a coffeeshop with my notebook and work on it there.