I'm learning the Damaru. we brought two back from Darjeeling - they are used in Hindu and Tibetan ceremonies. Shiva's drum - good spirit catcher, and it encompasses the universe, seen and unseen, past and future - the hour-glass.
interesting that it is not so easy to play. to keep both balls banging on alternate sides ... one ball keeps falling. there is a special rhythm consistancy to it. Ours don't have the handle, instead a piece of cloth one grasps in the hand - great when its working!