Musk Ox is a fantastic instrumental chamber folk project from up in Canada. I recently stumbled on these guys and their guitarist Nathanael Larochette from some collaborations he did with the (now defunct, but often brilliant) Oregon-based post metal/neofolk band Agalloch. Here's a neat documentary on the making of their album Woodfall.
Another cool project is the acoustic spin off that Nathanael did from the last Agalloch album.
His solo stuff is great. Music about trees and such.