This is the first single off the Earth section of Thrice's Alchemy Index Vols. III & IV album, released on the April 15, 2008. The Alchemy Index Vols. I & II (released late last year), and Vols III... more inside

Really nice song, also the OP to the anime Bokura No. Here's a higher quality version I can't seem to be able to embed: http://www.veoh.com/videos/v9540295eQ25R5ah