First there was the Mini. Then the Smart Car. Can automobiles get any smaller? Quite a bit smaller, according to scientists at Rice University (Houston). They recently produced the first nanoscale vehicle with an internal motor.
The nanocar measures just 3-by-4 nanometers, about the same width as a strand of DNA, but much shorter than DNA. About 20,000 nanocars could be parked, side-by-side, across the diameter of human hair.