Noticing this overlap caused me to create the Nexus book, as an unscientific method of mapping out these social intersections. The Nexus Book is a party game that has been going on since September 1997. Each page is a separate category representing a social group, interest, or activity. If you identify with that group, sign your name on that page. If you don't know what it is, then it's very unlikely that you're part of that group.
Since the book has been in existence for quite a few years, and has been brought to many disparate social events, the social mapping it facilitates is quite entertaining, especially when people see the names of old friends that they've lost track of in it.
It would be a natural for an online application and I've even posted some ideas on the subject. While many of the online communities are similar, I don't think that any really take full advantage of the potential.
In theory, people would add categories to the nexus book which have a
high overlap with other categories, since the goal is to find social
intersections. Many of the categories are those, and many seem to be
examples of folks trying to find the most obscure categories they
can. I collected a snapshot of the categories.
Copyright (C) 2005 Larry Colen
Most recently modified by lrc at Wed Aug 17 22:06:25 PDT 2005