This illusion is just a matter of perspective
 

SIDEWALK SPHERE: Created in Paris by Francois Abenalet, this ingenious sidewalk installation goes beyond the usual chalk drawings by incorporating actual grass and trees. It's a classic example of anamorphosis -- a distorted image that only takes its "proper" form when viewed from exactly the right angle...............

GEORGE WASHINGTON: America's first president gets a little homage in this illusion, which includes both a picture and a signature that work equally well when viewed upside-down...............

http://l.yimg.com/a/i/us/ga/buzz/fea...sphere_590.jpg

http://l.yimg.com/a/i/us/ga/buzz/fea...sphere_590.jpg

GEORGE WASHINGTON: America's first president gets a little homage in this illusion, which includes both a picture and a signature that work equally well when viewed upside-down.

http://l.yimg.com/a/i/us/ga/buzz/fea...ington_590.jpg

HIDDEN ANIMAL: Can you spot the creature embedded in this tree? If not, click here for a little help.

http://l.yimg.com/a/i/us/ga/buzz/fea...n_tree_590.jpg

IMPOSSIBLE ROOM: LEGO mastermind Henry Lim has used the plastic blocks to create a convincing three-dimensional version of M.C. Escher's famous mind-boggling lithograph, "Relativity."

http://l.yimg.com/a/i/us/ga/buzz/fea...escher_580.jpg

Wow! Great to see these pics.