Volkswagen has in some systems with navigation the ability to download up to 18 GB of music to the HD. Most of the entertainment systems have Bluetooth connectivity to stream music from an iPhone, MDI interface to directly connect an iPhone or iPod and SD card slots in addition to conventional CD players.
Fantastic German made Music Server for my Car
I was shocked the other day to find that my car has a music server as part of the audio system. Who knew? I was clearly clueless. I'm sure a lot of new cars have this feature but I accidentily discovered it the other day when I put in an Andrea Bocelli cd for my mother-in-law (it was going to be a long drive with the family) and there was a message "do you want to record cd". Of course I said yes and I have to admit it's very cool, convenient and sounds pretty damn good. I have loaded the hard drive up with lots of varied and fun music for long drives.