The air force has wired together almost two thousand playstations at wright-pat. The article doesn't say what OS they're using, or if they're running code on the graphics chips.

http://www.airforcetimes.com/news/2010/12/air-force-playstation-3-supercomputer-122410w/

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“The aeroplane is fatally defective. It is merely a toy—a sporting play-thing.  It can never become commercially practical." -- Nikola Tesla