This is a cool video. I was watching this the whole time, wishing I could hear the director talk about this shoot. Guess they did the AMA today!
Damian Kulash is the director here's him answering where his ideas come from:
lots and lots of drugs. that's a joke. kids: don't take drugs. also, adults, don't take drugs. unless drugs are your thing. then, I guess, go ahead and take them. Especially if a qualified physician has told you to. link
I don't know where the ideas come from. They come from the heavenly kingdom of ideas, which is a place I spend a lot of time trying to break into.