Planter Turns Pee into Fertilizer: Go to a big city that limits public bathrooms for "Customers Only" and you're sure to smell the distinct aromas of urine emanating from alleyways and building corners. Everyone pees. So why not use that liquid to nourish a city's plant life? That's what a team of designers in San Francisco wants to do. They've come up with the PPlanter, which transforms pee into fertilizer. The team, which entered their urban biofilter into the San Francisco Urban Prototyping Festival, are targeting homeless people and beer drinkers who really gotta go. At the PPlanter, men pee into the urinal; ladies use a "disposal funnel." A bamboo filtration system converts it into food for plants. An opaque stall door gives users some privacy.