Itty-bitty carbon rods.

Among materials scientists, the watchword is "nano"-the Greek prefix meaning one-billionth. They're chatting about nanowires, nanotubes, nanospheres. . . and now nanorods.

Charles M. Lieber, a chemist at Harvard University, and his colleagues are cooking up batches of rods that measure only 2 to 30 nanometers across and 1 micrometer long. The rods are composed of carbon in combination with various other elements, such as silicon and tin.

So far, the chemists have fabricated a "large family of chemically distinct, carbide nanorods." By changing the brewing broths and growth conditions, Lieber's team can concoct helical and sawtooth shapes, which he believes may have interesting applications.

Like what? For starters, he points to potential uses in investigating quantum physics and in building more complex nanostructures. Sending electricity through helical rods could create a tiny "rotating magnetic field," which researchers might use for sensing or manipulating atoms.

The little carbon spindles might also come in handy to reinforce alloys or ceramics, says Lieber, and perhaps even to improve high-temperature superconductors.