From France comes this idea via The Daily Good:

In the hierarchy of urban gardening space, the luckiest have access to outdoor plots or a nearby community garden. Then come a rooftop plot, followed by a balcony with potted tomatoes and herbs, and then maybe, a single basil plant sitting sadly on a stoop. Even people at the bottom of this pyramid are lucky compared to residents of dense urban neighborhoods and high-rise buildings that offer not even a smidgen of outdoor space, making any form of gardening an impossibility.

A clever project from French designers Nicolas Barreau and Jules Charbonnet elegantly transforms a window into a site for a micro-garden, bringing the potential for urban agriculture to just about any building.