Photos: Green tech giants

Whimsical remnants from the days when Google's campus belonged to SGI. Google opened up the space, turning multiple stories into a loft-like environment.

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Google's Building 43 is light and airy, featuring natural wood and recyclable carpet.

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Building 43 on Google's campus is a testament to Earth- and human-friendly characteristics. Exposed air ducts illustrate the company's function-over-form philosophy.

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Google's Building 43 features a prototype tent office.

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Electric scooters and bicycles make Google headquarters look more like a university campus than an office complex.

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Allowing Google employees to bring their dogs to work makes for a healthy, happy environment, say Googlers.

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Free, wireless-Internet-equipped shuttle buses take Google workers from San Francisco and other cities to Mountain View.

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An Olympic-size array of solar panels on the roof of Microsoft's Mountain View, Calif., campus.

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Office and hallway floors at Microsoft's campus in Mountain View are covered with carpet made from recycled materials.

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An outdoor water fountain sculpture at Microsoft's Mountain View campus.

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Open area at Microsoft's campus in Mountain View.

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A free shuttle transports Microsoft workers in Mountain View.

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