A friend of mine sent me this link that is so hawesome, I felt compelled to share it with everyone who reads my blog.
These guys are a very talented classical guitar duo, and they play the sort of beautiful classical music you'd expect to hear, you know Scarlatti, Bach, etc. But they also did an arrangement of the music from Super Mario Brothers, including the main theme, the "under the ground" music, and the music from when Mario goes swimming. I'm sure Nintendogeeks will tell me the precise names for those songs, but that's what we called them when I was 13 and played Super Mario Brothers for 30 hours a day with my brother, so there.
This is great stuff, so I hope you take a listen and enjoy it, too.