A gesture made when someone does something extraordinarily stupid. Much stronger than a facepalm
Man: Can you get herpes from a foosball table?
A response to a statement or action of epic stupidity with disastrous consequences, where a simple facepalm will not suffice...
Astronaut Alpha: Damn space can of Spam, I thought it was our NASA can opener, I would never have pressed the big red button if I had known it was the ships airlock release.
Astronaut Beta: FACENAPALM