I just learned about a new "web 2.0" start-up having launched. It's called edgeio and the core idea is "a classified listings system around content generated by edge publishers [...] giving individuals and businesses the opportunity to list content using their own websites rather than ceding control to a centralized service."

In other words, you tag your "anyone want to buy my old Powerbook" blog post with a "listing" tag and edgeio picks up your blog entry as a classified ad, aggregating it on their website.

We'll see how this fares against the real world.