Should we have a category which says that the subject of the article (a mathematician) collaborated with another mathematician who collaborated with another mathematician who collaborated with with another mathematician who collaborated with Hungarian mathematician Paul Erdős?
Well, according to the apparent CfD result, we should.
http://en.wikipedia.org/wiki/Wikipedia:Categories_for_deletion/Log/2006_Octo...
What is the limit of triviality? We have many people who love trivia, but I think we should try to keep trivia outside of the category system and keep only the defining characteristics for the articles.