Quite a while ago Mark has written a blogrollfinder [1] in Python. Finally the script brings up a list of People with blogs that his friends are reading, but not Mark himself, or in his own words:
And then it tallied up all the sites and sorted them by total number of links and compared it to my original blogroll and spit out a list of people whom my community is reading that I\’m not.
[1] http://diveintomark.org/archives/2002/06/02/social_networks
