It seems to me like there's a lot of potential to make some money and get helpful feedback at a pre-final draft stage.
I've been thinking about how to attempt a series where I work through an economic research project in real-time. Each step would be a post and the comments would serve as something like real-time peer review. I'm not particularly close to carving out the time for such a project, but I would like to try it out at some point.