I have just learned about Matter of Factor. I found an ad on the e-flux Time/Bank describing a crowdsourcing project. The MOF folks are running a site where they post a daily image composite of those that the participants submit. The crowdsourced images are to, however strictly, adhere to the task of making some kind of statement about the given word of the day. This word is the guide, and there are no rules for the submission. Anyone can be a participant by simply following the link to their site and selecting the respective Choose File and Upload buttons. While you're there, browse the previous days' results.
Here is a sample from February: