Brasil nostalgia - I was recently given a book on Brasil Graffiti which brought back memories of the urban art seen while peering out the car window.
One of my favourites is a guy who goes by the name Titifreak: A yoyo Champion from Sao Paulo and graffiti artist, animator and illustrator.

More of his art:
http://www.theglasslab.com/visual/art/

Some other artists can be found in this book:
http://www.graffitibrasil.com/GBlinks.html

His personal photo link can be found here: http://www.fotolog.com/titifreak/