"Curtain Door" by Matharoo Associates, India. 40 stacked sleepers of 10 inch-thick Burma teak are carved to integrate 160 pulleys, 80 ball bearings, a wire-rope and a counter weight hidden within the single pivot. When closed, it just looks like a huge, horizontally slatted wood door. Push on it and the wood feathers out into a beautiful sinusoidal curve, much like a curtain would.