Super Game Boy Commander
The Super Game Boy was a special cartridge that let you play Game Boy games on the Super NES using a TV set and a SNES controller.
Around the time the Super Game Boy came out in Japan, Hori released a special controller that partially simulated the look and the feel of the original Game Boy unit itself — right down to the speaker grille in the lower right corner. The resulting product, the SGB Commander, never saw the light of day in the US.
It was a controller themed after the original Game Boy to be used with the Super Game Boy adapter for the Super Nintendo.
You can buy it on Ebay for $34.99.