Have you heard of Frets on Fire? http://en.wikipedia.org/wiki/ Frets_on_FireI remember trying this out several years ago, though it didn't really havethat smoothe Guitar Hero feel.Yes, it's fucking terrible. It's also written in Java, which might partlyexplain the first bit...
I'm pretty sure it has been written in python (to prove one could write games using python), also there is FoFix a (better?) clone also python.
My kids do play FoFix from time to time. But nothing beats minecraft.