Warning, may contain a picture that could freak you out a bit.
http://news.sky.com/skynews/Home/UK-...His_Eye-Socket
So apparently this guy was totally blind (not born that way), they implanted a tooth in his cheek for a while, then moved it to his eyesocket, and now he can see again?
o...k...?
Edit: Apparently the tooth is just acting as a lens holder.