An invisible college
This wiki for complexity sciences provides an unusual variant of Kadushin's invisible college idea. The beauty here is that there are more private pages where one can keep track of collaborative projects, and more public cross-indexed pages of more general interest, but both are accessible to all members of the college, while relatively protected from search engines that index the contents of the wiki pages (i.e., low google rank).
Our wiki and some specific wiki pages are google-indexed, for example, simply because there are external links to them. But robots are prohibited from entering, visiting, and indexing the internal pages of the wiki that are not externally indexed.
Our colloquia, for example, are externally indexed at http://www.socsci.uci.edu/socdyn/ and can be freely indexed elsewhere. An author index, for example, is provided at http://eclectic.ss.uci.edu/~drwhite/center/cac.html
Given that the wiki is both a semiprivate workspace for those who log-in with their professional identity, and a collaborative workspace, I started, as any can, to construct lists of users, and index them by topic and discipline so as facilitate communication and collaboration. I also built a few lists of what I call virtual departments: listing those people in a given field that I collaborate with or would like to see in an ideal department that fits my general interests in the discipline or the topic. Others, of course, are free to do the same, with different lists. See, for example, the Virtual anthropology and Virtual sociology pages.