This summer, ten small libraries mysteriously appeared throughout New York City's Lower East Side and East Village. But who paid for them? Who designed them? And what was the point? In a short film published today, the creators finally answer our many questions about how the Little Free Library came to be.

The concept is based on something that's probably familiar to all of us: Take a book, leave a book. Organized by the PEN World Voices Festival and the Architectural League of New York, each library is a little different, and the designs were chosen out of a pool of 80 or so entries from a competition earlier this year. There's one down the street from our SoHo office, for example, and it looks like an oversized yellow hat. It's a really nice project, and something that truly seems altruistic. Who would object to pushing the concepts of reading and sharing, right? Especially when good design is involved. [ArchLeague]