What you're looking at is some cool sidewalk art by Kurt Wenner



He uses an old trick, anamorphic perspective, to give the illusion of depth when there really is none.

Our old bud Leonardo Da Vinci used this, as seen in a short .mov file
here.

Wanna know more? All you ever wanted (and probably more) is at
Generative Art

Personally, I just like the pretty pictures.