I've been listening to a new website, stereomood, which is where I first heard this song. I've heard of Sigur Ros, but had not been too familiar with their music.
Until I heard this. And totally loved it. Of course, I didn't understand what they were saying until I read a translation of the lyrics. And I was happy to say that I didn't really need to know the actual words because the overall feeling of the song didn't need to be translated.
The song is: Inni Mer Syngur Vitleysyngur
(Within me a Lunatic Sings)