
Dr Paul Rothemund at the
California Institute of Technology can make 50 billion smileys, each a thousand times smaller than the diameter of a human hair, with his technique. In a potent demonstration of his so-called DNA origami technique, Rothemund has created half a dozen shapes, including a five-pointed star, a snowflake, a picture of the double helix and a map of the Americas in which one nanometre represents 120 kilometres.