Back in the pre-casssette and 8-track 50s, Dodge and Chrysler (briefly) thought it was a good idea to offer a turntable option for their vehicles. The in- and under-dash units could only place special 16 2/3 RPM discs available only through Chrysler dealers (there were only about 45 titles made) and the owner's manual advised against listening to music at any speed except dead stop.
Needless to stay, the record-player-in-my-car never took off.
However, the time might be right to revisit this technology.
SEAT, a division of Volkswagen (pronounced SEE-at; think of them as being to VW was Scion is to Toyota), believes that no hip vehicle is complete without an SL-1200 installed somewhere in the vicinity of the boot.
Nice idea for the beach or the parking lot at McDonald's, but I wouldn't recommend throwing things down on one's and two's while at speed.