It was also brought up here 4 days ago or so: https://news.layervault.com/stories/18682-the-hamburger-icon-originated-at-xerox-
Wow, I always assumed it came from Path 2.0. I still suspect it may have popularized it, at least the use of it and not necessarily the notoriety.
I believe the biggest push for the hamburger icon came from the Facebook app, who sort of stole it from Path...
The video was originally found in the comments here: http://qr.ae/vpSot