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One of the interesting side effects of last year's stimulus bill was $400 million in funding for ARPA-E, the civilian, energy-focused cousin of DARPA. And in this week's first ever ARPA-E conference, MIT chemist Dan Nocera showed how well he put that stimulus money to use by highlighting his new photosynthetic process. Using a special catalyst, the process splits water into oxygen and hydrogen fuel efficiently enough to power a home using only sunlight and a bottle of water. . . .

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Combining this with Dean Kamen's water purifier would effectively make your house urine-powered.