Musée de Quai Branly's Vertical Gardens, Paris, France

Who said gardens have to be horizontal? Designed by botanist and landscape gardener Patrick Blanc, the Musée de Quai Branly's Vertical Gardens consist of three parts: a PVC layer, a layer of felt and a metal frame which provides a soil-free support system light enough to be hung from a wall.

The benefits? Improved air quality, lower energy consumption and extra protection from the elements. It's also a pretty good way to hide that broken drainpipe.