Try to count how many cubes there are in this image...
You will notice that the cubes can have a top as dark or side as a dark side, its pretty much imposible to count it...
Using a variety of different objects, this commercial creates a recognizable image from a shadow. This is actually a 60 second version of the 2007 John Lewis Christmas TV advert called "Shadows".
No matter which direction you move, it looks like Einstein's face is looking directly at you. This is an example of the hollow face illusion, which is a very powerful effect. You'll notice that the face itself is larger than life-sized. This illusion works best when the head is larger than normal.