When I listen to the ethereal music of Iceland's Sigur Ros I can't help feeling the same way that I do when I read great epics like Homer's Odyssey or Tolkien's Lord of the Rings. A pervasive sense that the world has been born or died or changed forever rings from the melodies. Part of this is the immense sonic landscape that the band creates—songs that sound like a place rather than merely a progression of chords. The Arcade Fire's "Wake Up" or U2's "Where the Streets Have No Name" are songs that feel epic, but Sigur Ros has a whole catalog. Make no mistake, the Iceland group seems to craft the anthems of mythology—the stories of fairies and elves.
I am not the first to note the similarity between the band and Tolkien. A review in Stylus Magazine from several years ago beat me to it. Sigur Ros, like Tolkien, creates their own language for many of their songs. Called "Hopelandic," it is often primal and eerie, yet still maintains a weighty significance. Sometimes Icelandic is interspersed with the imaginary dialect, but to my ignorant American ears, it blends together almost seamlessly.
Sigur Ros trying to think of the word for "epic" in Hopelandic.
If you are still unconvinced, try watching the video for Glosoli. Hoppipolla is also excellent. I tend to think that Tolkien would agree.