My reaction exactly, "this sounds a lot like Freenet". Although I wouldn't be ideologically opposed to the idea of getting another stab at the concept of FN, I think it's imperative for people interested in doing that to look at the history and challenges of that project. Even if we could get over the scalability issues (as the technology landscape has undoubtedly changed since then - "free" storage, larger bandwidth, faster processors... - we'd still have to wrangle with the unavoidable truth that nobody wants to risk hosting CP. I think you need to solve that problem, before you look at building such a system.