Street painting

http://www.hongkiat.com/blog/absolutely-stunning-3d-street-art-paintings/

This is a website on street 3d painting.  This is amazing because it takes advantage of how you see things, (perception) and plays on it.  What happens is the painter uses a longer version (so vertically it's longer than it will actually look like) so when looked at from the bottom, your eyes will try to compensate by compressing the image, giving the illusion that it's in 3d.  I've seen one of these during the military and it was the most mind boggling and fun thing I've seen during my tours.  It's cool how science and art can intermingle sometimes.