The Bubble Logic

MIT researchers created a microfluidic device in which tiny bubbles, while undergoing chemical reactions inside, function essentially like electrons in a microprocessor:

The team, based at MIT's Center for Bits and Atoms, reports that the bubbles in their microfluidic device can carry on-chip process control information, just like the electronic circuits of a traditional microprocessor, while also performing chemical reactions. The work will appear in the Feb. 9 issue of Science.
Bubble logic merges chemistry with computation, allowing a digital bit to carry a chemical payload. Until now, there was a clear distinction between the materials in a reaction and the mechanisms to control them," said co-author Neil Gershenfeld, director of the Center for Bits and Atoms.
Microfluidics allow scientists to create tiny chips where nanoliters of fluids flow from one part of the chip to another, undergoing controlled chemical reactions in different parts of the chip and replacing the conventional test tubes and glassware used for chemistry for centuries.
The technology has the potential to revolutionize large-scale chemical analysis and synthesis, environmental and medical testing and industrial production processes, but applications outside of the laboratory have been limited so far by the external control systems--valves and plumbing--required for its operation