The Song:Beck played this song live once on July 7, 2013. It seems to be brand new, and perhaps intended for the album(s) being hinted at for the end of 2013.
[2015 UPDATE: It did not end up on Morning Phase. Still no idea what this song is.]
I guess it could possibly be a cover or something; the recording isn't clear enough to make out much of anything.
Though it is kind of a cool hypnotic song, for sure!