Tiny turn-on

Researchers have made the equivalent of a tiny dimmer switch out of carbon
nanotubes—the tubular cousins of buckyballs. They found the electrical
resistance of a nanotube contact depended on its orientation on a graphite
surface. The nanotubes have a hexagonal atomic lattice, and the change in
resistance appeared as the lattice interlocked with the atoms of the graphite.
The effect might lead to molecular switches that vary current as they are
turned, says Mike Falvo, a physicist at the University of North Carolina
(Science, vol 290, p 1742).