If you haven't been to Overclocked Remix, you really should. All good-to-excellent fan remixes of videogame music. They've just completed a new project, OCR Vs Bad Dudes, and it's utterly superb. One remixer does the themes for a hero in a videogame series, another does the villain.
Why does that interest us, other than being frickin' awesome? Well, Monkey Island is one of the games remixed. Guybrush can be downloaded here and LeChuck can be got at here.
I won't spoil either, as they are both utterly excellent. You'll have a fangasm once you realize what they're singing behind the Monkey Island theme in Guybrush's mix. LeChuck's mix isn't quite as adventurous at first, then goes very cool fast. Check them out all out here.