Don't worry - not what the title may suggest. I propose a site from which members could share abilities. For example: I am in a band. We have made a record, but we need some album art. So in return, we search for an artist to some album art. The artist could be given our music free. Alternatively, a proprietary currency could be used which could be exchanged according to the difficulty/length of the task. This money could be exchanged for real money, allowing people to make money with the site. Bids could be made, with the task going to the lowest bidder.
Alternatively, you could help people by offering services free to everyone/certain people, with awards for the most 'charitable'. All sorts of services, from proofreading to instructional/teaching services could be exchanged. It could also provide a marketplace for independant music/films/literature without publishers etc.
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