I got hold of a CDTV recently for $30NZ. I managed to track down a CDTV keyboard, 1223 mouse, 1411 floppy and 1200 trackball all in nice Commodore black!!
The trackball is really good because it contains two standard joystick ports that allows you to use a standard Amiga joystick.
Any interesting device to get is the 1301 genlock which when installed has a S-Video port giving a better picture than the composite output. RGB is better but not everyone has a 1084S esp a nice black one!
The only thing missing is some nice CDTV software!