Its sells some inventory for media companies such as CBS Radio, which streams content on the Web from many of their local stations.

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YouTube, the most visited site according to video use, is free, as is the core part of Hulu, the Dow Jones and NBC-owned website that streams content from the major networks, along with participating cable partners.

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There are other products that do similar things -- from Apple's AirPlay, which streams content from an iPhone or iPad to your TV, to apps such as HBO Go that provide bonus content to enhance TV shows and movies.

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