How Many Optical Illusions Can You Find

I saw a short snippet of this video, by the group OK GO, earlier today and I had to find it in it's entirety. I've watched it over and over, trying to figure out how they did some of the illusions in the video. While I am certain this video won't change your life, it is pretty amazing when you consider all of the creativity and work it took to put it together and it was done in 1 take, just 1.

See for yourself.