Wow, some people have some serious hacking skills. That, and a lot of time. This guy built his own interface that allows him to connect the Guitar Hero controller for the Playstation up to his Commodore 64 on which he plays a Guitar Hero clone he calls Shredz64.
That’s very geeky… and cool!
Get more information at Toni Westbrook’s website and here is more about his Shredz64.