Faldinn

It takes approximately 1400 meters of yarn to make a simple sweater and at least twice that to knit a "fancy" one. It also takes 4pounds of clean fleece to make the yarn.

Written by Icelandic composer Jón Leifs in 1964, the piece called Hekla, Op 52, requires four sets of rocks hit with hammers, steel plates, anvils, sirens, cannons and metal chains to play.