Nocturnal peeing is a problem. It leaves an unpleasant stench that is surprisingly costly and labor intensive to clean up. For example: Paris scrubs 1,800 square miles of pavement every day. So, cities are working hard to find a fix: Amsterdam has retractable toilets that rise from the ground. San Francisco deployed paint that splashes it right back at you. Now Paris has introduced the Uritrottoir, which translates to “pavement urinal.” The top of this two-layer box is fitted with a urinal trough, and loaded with flowers growing within rich compost. The compost is started in the bottom box, which has a little portal that leads to straw—straw that you pee on.