Sigur Ros or Explosions in the Sky.
Both are bands that you have to listen to on a stereo to really get.
Oh, or Sunn O))). Which has to be listened to on a good stereo. A big one. And LOUD. And that's just what they do live, but, like, way louder. Loud enough to feel your chest shaking. And it sounds awesome. And they sound like cool people.
So three-way-tie between Sigur Ros, Explosions in the Sky, and Sunn O))).
Though I will be seeing EITS next month.