If you view videogames as not a way to have fun, but a challenge, something that you need to figure out how to do perfectly and then retire from, then I can see why you might like the Guitar Heronoid. But if you see videogames not as some elaborate math problem but as a way to have fun, well, you might just think it's a pretty stupid idea.
The Guitar Heronoid is a machine that looks like a robot that is able to play Guitar Hero perfectly. It's got a "brain" that reads signals from the Playstation 2, and hands that play the guitar controller perfectly in time with the game. Wow, how… fun? To be fair, this is a crazy DIY project, so I guess if you get off on building things and being way too geeky for your own good this could be more fun than actually playing the game like a normal person.