Today's silicon-based microprocessors are manufactured under the strictest of conditions. Massive filters clean the air of dust and moisture, workers don spacesuit-like gear and the resulting systems are micro-tested for the smallest imperfection. But at a handful of labs across the country, researchers are building what they hope will be some of tomorrow's computers in environments that are far from sterile-beakers, test tubes and petri dishes full of bacteria. Simply put, these scientists seek to create cells that can compute, endowed with "intelligent" genes that can add numbers, store the results in some kind of memory bank, keep time and perhaps one day even execute simple programs.

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