Before Sony made the PlayStation, they tried to team up with Nintendo. Together the companies would release an SNES CD add-on to compete with companies like Sega who were releasing CD-ROM upgrades of their own.
Needless to say, the system never existed...to the public. But gamers can still capture a price of history through an eBay auction is going on now for this SNES CD developer unit controller. Even if you don't plan on plunking down $3,000 to have this as your own, you can still appreciate it as a precursor to the modern PlayStation controller. Luckily Sony ditched the idea of six buttons and flipped this upside down design, because I can't imagine reaching those bottom buttons without dislocating my thumbs. Here's another shot: