The RetroUSB NES/SNES controller adapters enable gamers to easily attain a more genuine Virtual Console experience through the ability to use original controllers. Some hackers have gone even further, building custom circuitry into old equipment. Custom Nintendo themselves have contributed the Super Famicom Classic Controller to the cause of authentic retrogaming.
Raphnet's projects include not only adapters and fully-modded SNES and NES controllers, but also N64 solutions. Raphaël Assénat has documented the process of hacking custom controllers with custom circuit boards to allow them to work as Gamecube Controllers, and also sells adapters that let you plug N64 controllers directly into the Wii. People seem to like that controller for some reason.