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Google today rolled out a Labs feature that allows you to quickly send SMS messages via Gchat—perfect for continuing to antagonize your contacts with your witty links well after they leave their computer.

Just go to the Labs area in preferences to turn it on—you can just enter any number in the Chat contacts bar, or add numbers to your existing contacts. Unfortunately its only the States at the moment, and so we're looking out for when Google makes this available everywhere else.
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