Iceland Academy of the Arts design student Ari Jónsson has designed this water bottle using algae powder—the bottle is biodegradable and retains its shape as long as there is water inside of it, but starts to break down once it is empty. While the process of making it sounds pretty involved, and it's kind of hard to imagine these replacing plastic bottles in the near future, it's a very cool concept nonetheless.
• Ari Jónsson uses algae to create biodegradable water bottles [Dezeen]