What about freenet? They hold many of the same ideals about a 'free' (freedom) Internet, but have gone about it a somewhat different fashion from what you describe.

Your suggestion is somewhat intriguing though, and sounds (at least to me) like it has the potential to be a lot quicker than freenet's method of guarding anonymity (all my experiences with freenet are that it is quite slow to access due to what I understand is the way files are retrieved).