I have always wanted to do this, and then I did it by accident. (This is about blog stats - please feel free to skip if you are not a techie!)
Technorati provide blog ranking stats (www.technorati.com) It's a bit of a mission to find out the rankings of the South African religion blogs that I am interested in, but there are a few that I check once in a blue moon. Blog rankings are based on what Technorati calls authority. Authority is calculated from number of hits to the blog, how often posts are created and links from other posts - I'm not sure if they use anything else. This works quite well because it stops inactive blogs topping the ranking. You also can't manipulate it with 'link farms' because links must be current.
All the South African blogs were sitting at around authority 100. Then Steve Hayes linked to me from his Notes From Underground Blog. I started checking Technorati - yes! My blog went up to authority 408. Then I happened to link back to Steve's Khanya blog. He linked to Cobus van Wyngaard from Khanya and I also linked to Cobus. Now Steve's Khanya blog and Cobus's blog are both around 400. And I've just linked to them again, so let's see what happens.