When it comes to controllers, I try to steer clear of third-party options, as I've never once had a better experience with a knock-off versus the real thing. On the other hand, I gladly welcome any and all limited edition pads or goofy peripherals by the console makers themselves. The NES Advantage? Manna from heaven.
Even though playing with unconventional controllers may not always be ideal, some of them simply look damn amazing. Just take a glance at the 25 controllers in this CVG gallery, stretching all the way back to the NES age. A friggin' Wu-Tang controller bundled with Wu-Tang: Shaolin Style? Hardly practical, but deliciously kitsch.
There are some prototypes that never saw the light of day, like the incredible Twilight Princess GameCube pad. Others were fairly progressive for their time, like the NES Hands Free Controller for quadriplegics. And some are still readily available, like the Sonic Screwdriver Wii Remote for an acceptable $20.
I've added a few to the gallery below, but you ought to hit the link for the full spread. Do you actually own any of these oddities?