I wonder if anyone could help me uncover the number of mailing lists there might be in the world?
The trick to this question is that in addition to public lists that are hosted on systems such as YahooGroups, or legacy university Listserv lists held over from BITnet, there are an ever increasing number of lists that are hosted on organizational and personal servers, which fly underneath the casual research radar, and there are an incredible number of newsletters and notification systems, like GetActive, that don't fit the classic list definition. The other trick is being able to recognize and know rebranded products. DGroups, which serves international NGOs, is a customized version of Lyris. Lyris has a huge customer base in the NGO sector, apart from their corporate contracts. Also, there is still a HUGE installed base of majordomo 1.x systems, even though the software is out of date and inadequate for most modern mailing list needs. Inertia keeps them going. Mailman, a Free/Open Source mailing list manager, is probably the most popular software program for those setting up lists on their own servers. Also, most ISPs who give you a selection of services for a flat monthly fee include the ability to setup Mailman lists as one of the built-in features of an account. Finally, there are also a bunch of lists running on less popular or more specialized software that are hard to find, which used to be included in directories like Tile and Liszt but aren't anymore (listproc, ezmlm, etc.). Places where the majority of ad-supported lists are hosted: http://www.yahoogroups.com http://www.topica.com Most popular commercial list software packages/providers: http://www.listserv.com http://www.lyris.com Most popular non-commercial list software: http://www.gnu.org/software/mailman/mailman.html http://www.sympa.org http://www.greatcircle.com/majordomo/ Most popular newsletter management system: http://www.getactive.com Art