Projection photography by Lee Kirby. This could be cool with places in a famous country and then the skyline in black and white (portrait)
:: Arquitetura do Vale ::
Les chats de Willy Ronis, Paris, 1954 (Willy Ronis) black and white
A best source for optical illusions, brain teasers and eye tricks.This great collection has every type of illusion that you can possibly think of !
Here's the photoshopped optical illusion cow.