What do audiophiles listen in their cars?

I know this is not a car audio sight, but it would help me out a lot if I could get input as to what the discriminating audiophiles listen to in their cars.

If you can give me a detailed list of the system, I would really appreciate it - I am starting an affordable Hifi shop that includes car audio.

Thanks a mill. in advance...
Apart listening to my wife, I sometimes listen to the stock Bose sound system which gives me a pretty good listening experience (This is the only Bose system that I have, not by choice). I wouldn't spend a ton on upgrades or none at all since I will and can not enjoy serious listening whilst keeping an eye on traffic so it is mostly easy listening and Jazz.
Rok2kid: I agree on the Avalon. My 02' has a cassette and I enjoy it quite often. Great car as well.
I will say though, that my wifes Acura TSX has a tremendous system with the DVD-A. It really is great sounding.
And as others, I would not change the stock system in my cars.
Tore out the dreadful "Premium Bose" system in my 08 Z06.
Installed a Kenwood DVD/NAV system with IPOD interface.
Added Dynaudio component speakers, Alpine 600watt amp, and JLAudio subwoofer. Dynomat in both doors.
System sounds incredible with pin point imaging and nice tight bass!