While Second Life was struggling to find a business model for success, companies such as Shanda, which were influenced by South Korean game publishers, built thriving virtual goods markets.

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In the case of bitcoin, a strong case can be made that, even with secondary markets, certain virtual currencies lack the legal elements of material value and property.

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This fever was reflected in higher secondary markets prices for these virtual goods.

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But Paulson and other banking regulators sat tight until the subprime mortgage market imploded in the summer, bringing down with it a few hedge funds and, more significant, putting a virtual freeze on the fixed-income markets.

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Listen to Scott Redler navigate the markets in real time on the Virtual Trading Floor.

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Virgin is a so-called virtual operator, which leases network capacity from an existing operator and markets services under its own brand.

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In its tenth year of operations, Hillcrest has designed its newest products to make the integration of natural user interfaces possible in a wide range of markets, such as television and digital media, smart boards, virtual reality systems, and many others.

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Virtual day traders' individual trades may be relatively small, but en masse day traders can make waves in the markets - but they risk being swamped by the same market forces such as a sudden drop in value.

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