Acid Mothers Temple, Sangre Cavallum, Wolfmangler, Cadaverous Condition, Six Organs of Admittance, Comets On Fire and Sunn 0))). Google them here and you'll find most of them on my playlist (Google them in a few weeks time and you'll find all of them there). They are members of what The Guardian alleges to be the new rock underground, in an article by Julian Cope, who should know. He's been championing this sort of stuff for years on Head Heritage which remains a great starting point for launching into this netherworld of doom-merchants, gnostic meditators, free-fuzz sonic experimenters, or, as Cope puts it for his mainstream readers, 'open-minded heavy metallers'. It's a wonderful world.