Projects like seti@home  have been around for awhile, I'm not sure how long. There are a few others that I can't seem to find right now. The articles about Google's cloud computing  got me to thinking, why isn't there a crowd-sourced general purpose version of these networks?
Some company creates the libraries and test facilities for writing MapReduce  programs. Then they provide a free program that people can download and run, like in . Companies would pay to have their programs run on the network, and the profits would be passed on to the individuals who's computers ran some of the processing ...
I know there are a lot of tiny details to get right, security, validation of results (IE, rogue machines purposely calculating invalid results quickly to game the system), but it feels like it could be insanely profitable.
Someone has to have thought of this already. If someone out there knows of this, please let me know.
 - http://setiathome.berkeley.edu/
 - http://www.abetterkindofangry.com/2007/12/googles-algorithms.html
 - http://en.wikipedia.org/wiki/MapReduce