Many purifiers, both industrial and residential, clean the air by giving pollutants an electric charge and trapping the staticky gunk with oppositely charged metal plates. Humanscale's tabletop Humanair replaces metal with strips of paper coiled into a foot-wide spiral. The paper attracts dirt like metal plates do, because charged lines of metallic paint run along one side of the strips. But the nonconductive layers of paper can be packed just 0.06 inch apart without creating sparks, so the paper traps more grit. It squeezes 14 square feet of filth-catching surface—at least twice as much as other electronic home purifiers—inside a 15-by-13-by-4-inch case.