To ensure that the unit stays DIN-sized, which is essential if you want it to fit most cars, then either the flap would have to be very thin or you'd have to lose part of the Empeg unit to make room for the flap within the DIN-sized cradle.

I think a slot in or over bit is more feasible. Nice idea though. :)

Cheers,

Mark.
(Now with 63 CDs loaded onto a 4Gb unit leaving 812Mb free, which is still on target for about 80CDs on the smallest/cheapest unit)