Lifehacker - Back Up and Play Your Wii Games From an External Hard Drive - Wii
http://lifehacker.com/5263589/back-up-and-play-your-wii-games-from-an-external-hard-drive

A disc that never leaves the case can never be scratched. Save your Wii games to an external hard drive with this handy tutorial for speedier and scratch-free playback.