ZERO-DIMENSIONAL METALS are studied by physicists at Harvard. In general, reducing the dimensionality of an object makes its quantum nature more manifest. In a semiconductor, for example, confining mobile electrons to a plane (2D) or a wire (1D) or a dot (0D) enforces an ever sharper limit on the allowed energies, and this can be exploited in producing compact and highly controllable electronic devices. The Harvard scientists (contact Dan Ralph, now at Cornell, ralph@msc.cornell.edu) have succeeded in attaching leads to 10-nm-sized metal particles; this allows them to apply a gate voltage which turns the tiny particle into a transistor. Unlike semiconductor dots, the metal nanoparticle can be made magnetic or superconducting, allowing forces inside the sample to be analyzed. Indeed, with this speck of aluminum, the discrete quantum-mechanical spectrum of electrons in a metal have been measured more accurately than ever before. One can watch the electron spectrum even as magnetic fields break up the superconducting state. (D.C. Ralph et al., Physical Review Letters, 26 May 1997.)