Advertising that also serves the greater good? Now that’s something different. This floating billboard is covered in Vetiver; a perennial, non-invasive grass which has found popular used treating wastewater; even when it’s high in nitrates, phosphates and heavy metals. In this case it’s been used to spell CLEAN RIVER SOON, a hopeful message along the highly polluted Pasig River in the Philippines. It’s creators say systems like this have been shown to clean between 2 and 8 thousand gallons of water per day, and simultaniously, it creates a much more inviting place to stroll.