...and
To stop your car and turn it off you'd press 'start'
You won't be able to drive in the wet
You'd only be able to drive it on their roads
To use the emergency services if your car breaks down you would have to be in a perfectly functioning car to gain access to their helpline
A random Citreon driver would be able to transfer his engine characteristics to yours and steal your BMW engine without you knowing
We'd all be driving the same car
Everytime you started your car up, a hoard of windscreens cleaners would offer you free support
Drivers would use their car for having sex - oh, they already do
WeeJohnyB