Optical Illusion

This is not my photo. This is making the rounds on the internet.

" This is the craziest thing I've seen in a long time. You have to get out of your seat and walk away from your computer. People may think you're crazy. But it's well worth it. ;) "

"When you look at this picture close up, you see Albert Einstein, but if you stand about fifteen feet away, the picture will become Marilyn Monroe. "