Google wants more and more of the time you spend on the Web, making money mostly from advertising.

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In fact, from a June 2010 web article, Making Money Online, Part 2: Microworking on the site The Quill, a number of other crowdsourcing sites ShortTask, microWorkers, and DeskLancer suffer to a more observable degree from spam crowdsourcing.

FORBES: Spam Hurts Crowdsourcing But Can't Kill It