It's hard to imagine something which folds into a board on your wall so easily would be able to hold a lot of water, but the foam-like rubber is light, flexible and somehow super sturdy too.

Not only has Bathboard been created to save space in teeny tiny apartments, it's also a good way of stopping owners from using too much water, as the bath fits to its content so that you don't add more than you really need.

Via Yanko Design.