I've just discovered these guys. I understand they are genre-open-minded, doing BG, as well as stuff like this. It's really weird-- there was a local band in Prescott, AZ named Limbs Akimbo, and they did this same exact kind of Jam/Calypso, or what would you call it? Another band I like in this vein is Rusted Root (though I don't remember seeing any mandolins there...)
edit to add another one, completely genre-bent: Beneath the Blossoms.
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