Fjögur píanó by Alma Har'el
Taken from the "valtari mystery film experiment"
more details: http://www.sigur-ros.co.uk/valtari/videos/

Valtari is available to purchase now: http://www.sigur-ros.co.uk/valtari/buy/
Alma Har'el - winner of Best Documentary Tribeca Film Festival - www.bombaybeachfilm.com