Few people have beaten the drum for, uh, the drum as passionately as Mickey Hart. The Grateful Dead stick-handler has illuminated and chronicled drumming from the Big Bang through the latest in electronics in various recordings ('Planet Drum'), books both personal and historical ('Drumming at the Edge of Magic') and through his work as an ethnomusicologist and preservationist with the Library of Congress -- but never with more creativity than in a series of collaborations with tabla master Zakir Hussain, now spanning more than three decades.