This is really only a note to myself, but it may be of interest to others.
Metroid Database is a website dedicated to, you guessed it, the Metroid series. My personal favorite is Super Metroid for the SNES. It ranks up there in my top five games of all time.
Anyway, I wanted to hear the music from the Maridia region of the game which led me to the Metroid Database where I found rips of the soundtrack. If anybody else is interested, it can be found here:
http://www.metroid-database.com/sm/music.php
I had forgotten about the space-funk Brinstar theme:
Here's the aforementioned Maridia music, which isn't as interesting as I recall. Still, I imagine it could sampled and put to good use in a beat: