A company called Terracycle, featured last year on National Geographic's series Garbage Moguls, recycles pens, candy wrappers, tooth brushes, and even that supposed scourge of the waste bin: dirty diapers. The materials are remade as park benches. Any young athlete has already noticed the recycled tires in her playground mulch, turf cushioning, and track-and-field surfacing; but tires also appear in cosmetics and in the shock absorbers that now grace many highway guard rails. Even wax-coated cardboard, long considered a contaminated recyclable, can be repurposed as a fireplace wood substitute.