With the exception of pre-moderated mailing-lists, content quality varies widely, but even in the most high-traffic forums, one can still find insightful posts. You may also want to view the UFO blogs.
Whitley Strieber's unknowncountry.com (regardless of what one thinks about Strieber's own stories, due to his tremendous publicity, this forum attracts people who think have had similar experiencers)
CosmicView group at MSN embraces the stories (or tales if you will) of "contactees" (people who claim to have been contacted by extraterrestrial beings), with the goal to "help people understand WHERE extraterrestrials and UFOs come from - WHY they visit Earth and WHAT we can do about these visitors". Has a library with interviews and photos of claimed contactees, such as Paul (Apolinar) Villa (US), Luciano Galli (Italy) etc
Ed Mitchell UFO forum astronaut of Apollo14 mission, maintains an UFO forum on his website
[Closed since Oct-2007, for subscribers only] virtuallystrange.net UFO Updates mailing list archive, with over 67000 messages archived since Dec-1996. Active members include many veteran Ufologists, with several decades of UFO study "under their belts". Reviewing the archive of prior years' posts can be a gold-mine, but the list is currently basically void of technical discussion.
so others can find it too!
Subscribe in a reader to an aggregate feed of UFO news
