The rules don't apply to individuals who simply use virtual currencies to purchase real or virtual goods.

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With its full head and motion tracking support, the technology is a milestone for real-time gaze interaction with virtual avatars or 3D gaming applications.

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"We are very interested in music where you have real instruments on stage and virtual sound sources, which can be coming directly from the computer or transformed from the real-time recording of instruments onstage, " he says.

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They tested 600 subjects when surrounded by red, blue or neutral colors in both real and virtual environments.

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Hollywood studios or video game prodigies can build photorealistic real-time virtual worlds.

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In addition to viewing 350 Barbie dolls and other displays, visitors can strut a long runway, "bake" virtual cupcakes in a pink kitchen or eat real ones in the cafe.

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Entire virtual economies have emerged, assigning real-world monetary value to items or skills in games.

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Visitors will experience an extensive virtual environment before gaining brief access to one or two of the real caves.

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But what if you could tag a real-life building with a photo of yourself or some other content, as a form of virtual graffiti?

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Researchers at the University of Manchester are turning to virtual reality once again, not to have another go 'round at proving whether telepathy is real or not, but to help individuals with amputated limbs recover from so-called "phantom limb pain, " a sensation wherein amputees appear to feel pain in their lost limb.

ENGADGET: Researchers turn to VR to treat phantom limb pain