Bad Brains, Operation Ivy, Black Flag, Husker Du, The Flaming Lips, My Bloody Valentine, Pavement, Sonic Youth, even the Talking Heads - nobody I know has heard of these bands (or, if they've heard of them, they've never listened to any of their stuff). However, to be honest, I'm not huge at seeking out the most obscure bands possible. All the bands I've sited are quite underground, but they're critically acclaimed in their respective genres or have attained "cult" status. I'm of the opinion that if something is really good, odds are someone else has recognized this and shared this with the world.