A team of physicists from the Paul-Drude-Institut für Festkörperelektronik (PDI) and the Freie Universität Berlin (FUB), Germany, the NTT Basic Research Laboratories (NTT-BRL), Japan, and the U.S. Naval Research Laboratory (NRL), United States, has used a scanning tunneling microscope to create a minute transistor consisting of a single molecule and a small number of atoms.
http://www.nanotech-now.com/news.cgi?story_id=51890