On page 35 of the January 16, 1995 issue of Electronic Engineering Times, there is an article titled "Sub-0.1-micron logic sought". It describes a digital logic technology which relies on an arrangement of single-electron quantum wells which is bistable (can retain a 0 or 1), and which can influence adjacent cells. They propose building a cellular automata implementation of logic gates, and claim that they can implement any functionality possible in Field Programmable Gate Arrays. The article has diagrams showing implementation of a two-input AND as well as two input OR gates. One of the interesting properties is that information is not propagated by the flow of electrons - it propagates through the influence of the state of each neighbor, or as they say it "electrons do not travel through the circuit; only the digital information does."
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