Artecnica is one of the pioneers in the burgeoning field of sustainable design. For five years, they've been producing a line called Design w/ Conscious. Obviously, the designs use recycled and sustainable materials. But what's more, they source the manufacturing in poor communities where jobs are scarce, including Brazil and Guatemala.
TBWA/Chiat/Day saw those efforts and proposed a collaboration: They wanted Artecnica to take charge of recycling their billboards. Two years later, the first two products have just been introduced.
With the first product, the idea was to make the largest bag possible from the smallest amount of material. They start with a single sheet of material--either leather (less sustainable!), or recycled plastic, made from the discarded billboards of some of TBWA's biggest clients (hint). That sheet is then cut with a pattern of slits--which allows the it to transform into an expandable bag. Full, it can carry 33 pounds. Empty, it lays flat for storage. (As one commenter on DesignBoom notes, this idea is actually common in Japan, in carrying bags for hot food.)
The second product is a series of carrying cases, fashioned from billboards and sustainable cork. Again, these were made with as little material as possible, but this time, the inspiration was the common envelope. The cases come in three sizes, the largest of which is a clutch:
[Via Artecnica and Designboom, which has more images]