Mailing Lists
Cyndi Howells once again does a fabulous job in pulling together an extensive list of mailing list resources. They are arranged by category. This includes topics like adoption, surnames, newbies, military, archives of mailing lists and more.
Mailing lists are a free form of communication on specific genealogical or historical topics. You subscribe and participate via e-mail. Rootsweb has links to almost 20,000 mailing lists. They are categorized by surnames, geography (US and International), and other. This is first stop shopping for mailing lists.