Rice University scientists have constructed a "nanocar," consisting of a chassis, axles, and four Buckyballs as wheels. From a press release:
"The synthesis and testing of nanocars and other molecular machines is providing critical insight in our investigations of bottom-up molecular manufacturing," said one of the two lead researchers, James M. Tour, the Chao Professor of Chemistry, professor of mechanical engineering and materials science and professor of computer science. "We'd eventually like to move objects and do work in a controlled fashion on the molecular scale, and these vehicles are great test beds for that. They're helping us learn the ground rules."
The nanocar consists of a chassis and axles made of well-defined organic groups with pivoting suspension and freely rotating axles. The wheels are buckyballs, spheres of pure carbon containing 60 atoms apiece. The entire car measures just 3-4 nanometers across, making it slightly wider than a strand of DNA. A human hair, by comparison, is about 80,000 nanometers in diameter.