Sounds like a silly question, but apparently that's where we're heading as a society. Engadget reports that the 2009 Hyundai Elantra Touring model will have a USB port, which everyone is presuming will allow you to bring MP3s along and plug them straight into the car stereo. Hyundai hasn't released any details confirming this as of yet.

Granted, this is another interpretation of "mobile media" we don't usually discuss here. But part of the reason why we're so adamant about removing DRM from online media is that you can do exactly this kind of thing: buy a song once and then listen to it wherever you want, be it your cell phone, your car, or on your computer.

2009 Hyundai Elantra Touring to feature USB port [Engadget]