Thanks goes to Beeza44 for getting me hooked on NPR/WNYC's On the Media which is where I heard about this in their April 20, 2007 podcast (skip to 18:46 to get right to it or listen to another interesting article about the Virginia Tech Tragedy). From the On The Media website:
Clearing The Air
In January, South America’s largest city officially banned outdoor advertising. Billboards, neon signs, bus-stop ads, even the Goodyear blimp - all were suddenly illegal. Folha de Sao Paulo reporter Vinicius Galvao describes seeing his city as though for the first time.
On a completely unrelated note does anyone have a school bus for sale? Cause I have a new project.