Have you seen this guy's 3D sidewalk art? Well, it's 2D... but done in such a way that if viewed from a certain angle, the image will trick your eye into thinking that the object depicted is "on" the sidewalk.

Make sure you scroll down far enough to see what his artwork looks like if photographed from the "wrong" angle!

[I've seen it before but it deserves another shout... extremely cool. -k]

Impact Lab - Amazing 3D Sidewalk Art Photos