It’s a smart idea, allowing end user communities to create their own slices (or rankings) of the Google index. I would say vertical but in fact this stuff is likely to be as much diagonal, fuzzy or oblong-shaped as it is vertical.
I am experimenting with two Coop engines.
The first is Trends Potter which is giving better rankings to trend spotting and futurology sites.
The second is Web2.0 which is
a desparate attempt to raise venture capital an index of web2.0 related blogs and companies, mostly culled from TechCrunch’s list of firms.
Both Coop engines are open to new collaborators. You can just visit and improve the engines by adding more sites as well as adding keyword refinements. Maybe we’ll create something useful.