Super Game Boy for PSX

Play Game Boy games on old model PlayStation's with the GameShark port in the back.
The games with Super Game Boy enhancements will even have the custom borders.
The downside is that the Game Boy game's audio is not emulated.

Selling for $8.00
http://www.ebay.com/itm/New-Playstation-PSX-Super-Gameboy-Game-Boy-Booster-Innovation-/170905139265