I imagine some of you already know about these sites, but for those who don't, I have found a couple of sites that sell adapters that let you use actual NES, SNES, N64, Genesis/Mega Drive and SMS controllers on the Wii. They adapters plug into the Gamecube controller ports on the Wii, and then you plug the controller into the adapter.
For NES and SNES adapters - www.retrousb.com
For N64, Genesis/MD and SMS - http://www.raphnet-tech.com/products.php?cmd=list&categor...
Enjoy!
brooks83