I use a flat visor-type CD holder to park CD's after inserting a new one to listen to while driving. It would'nt fit over the visor, so I affixed it with velcro to the driver's side of the console about knee-high. It's barely noticeable and I put them back in the CD case when I get home.

 

Two stacks of CD's in their diamond boxes fit perfectly in the small cubby holes behind the seats. I keep about 8 of them in the one on the left, which is reachable from the driver's seat. The door keeps them from flopping around. I don't mean the big lockable one below.

 

Be carefull storing hard/brittle plastic on the visor. When I wrecked my Z28 I had cassettes on the visor. One of them cut my nose down the to bone (cartilidge). My nose hit the cassette, split it, and the resulting sharp edges cut me.

I know it was sort of a fluke, but I still never keep anything hard/sharp on the visor.

Just my $0.02