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List of Crowdsourcing service providers, categorized as Services Platforms, Idea Platforms, Competition Platforms, Content Markets, Content Rating, Crowdfunding, Crowdsourcing Aggregators, Cycle Sharing, Data Sharing, Distributed Innovation, Innovation Prizes, Microtasks, Prediction Markets, Questions, Reference Content, Service Marketplaces. There is also a list of common crowdsourcing tasks and examples.
(image by crowdsourcingresults.com, released under Creative Commons Attribution Share-Alike) (via napo)