t's their nanostructure that makes many crucial materials useful, and chemical processes essential to everyday life routinely do their work on the nanoscale. There's a lot more to nanoscience than building itty-bitty widgets.

Nature's robots

For 15 years, ever since K. Eric Drexler's Engines of Creation launched the nanocraze, the field has been plagued by sci-fi notions of tiny robotic "molecular assemblers" running around shoving atoms together. But as buckyball pioneer Richard Smalley remarks, molecular assemblers have long existed: "We call them catalysts."

Catalysts are "helper" substances that promote chemical reactions without themselves being consumed. Nature's catalysts, enzymes, assemble only specific end products. Industrial catalysts are rarely so precise.