This bottle that separates drinking water from ocean water doesn't exist yet--except in the renderings you see here. But it would be nice if it did. It could be a useful addition to a boat's safety equipment, ensuring the shipwrecked are able stay alive without resorting to their own urine.
The bottle was designed by a team from Yonsei University in South Korea, who recently entered it to the 2013 IDEA awards. The idea is simple: You pump a plunger at the top, pressurizing ocean water until it's pushed through a membrane at the bottom of one chamber. Fresh water then enters into another chamber.
"The Puri portable fresh water equipment has reverse osmosis technology," the students say. "This is the only product that can continually supply water when people get into marine disasters. It puts the best face on it when people get into emergency situations."
The students make a plausible case for what such a water bottle might look like, down to the materials for all the parts. Let's hope it gets built--there's definitely a need for cheap, portable desalination, and urine just doesn't cut it.