A Car Stereo Question

Do newer cars have an "audio in" jack, on the dashboard or center console, as part of their audio systems? Something you could use to connect an MP3 player thru the car's system. What auto brands, if any, have this feature?

BTW, I drive a 1998 vehicle.

Thanks to everyone.
I had a Mitsubishi 3000 that had an input on the dash. Many Blaupunkt after market units have an AUX input on the back and for $12 you can buy a cable adapter (eg, from Crutchfield) that lets you access this input.
I'm almost certain that GM (Delco) radios do not have this capability. Can't speak for any others.
Forget it! Buy after-market car audio and have it professionaly installed. There is no factory car audio that is worth the hole it came out of.