Water They Thinking? Unicef's Guerrilla Campaign
"Buy your dirty water here!" Unicef set up coin operated water dispensing machines in the city, but they weren't quite the water you want to drink. Each button had a different bacteria listed that could be in the dirty water that millions must drink in poor areas.
The machine was a cleverly disguised donation box for Unicef to provide clean drinking water for individuals and areas of the world that don't have access.