Update: Google Turns On Peer-To-Peer Computing App
Google has turned on a distributed-computing feature in its toolbar which will allow idle computers to donate idle CPU cycles to cancer research--and to Google itself in the future.

However, company representatives said the feature is actually a "beta experiment," and not available to the full community of users. The company rolled out the program to 500 beta testers earlier this year, and has since expanded the program to a second level of testing totalling about 1,000 users, a Google spokesman said.
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