Trust the Ferret, the Ferret is Wise

Anybody have any good suggestions for music like from Firefly? Because the music in Firefly was awesome. The music in Serenity wasn't bad, but it wasn't the same kind of awesome mix of cowboy/asian/middle eastern/etc music that Firefly had. There's the soundtrack, but that's only one disc. And it's not nearly enough if for background music if I end up running a Firefly/Serenity RPG, really. I have a little bit of international music that might suffice, but I need more. Suggestions, anyone?

Also, Steven Brust is apparently writing/has written a licensed book set in the Firefly universe. I'm excited!