The #mythgard community and #signum are definitely musts for fans of #tolkien or his circle of friends, the #inklings, as well as other medieval and speculative literature.
Mythgard includes free online seminars and discussions. There is also an annual conference, #mythmoot, in the DC/Baltimore area, as well as various smaller one-day conferences throughout North America and London.
Signum University is a masters degree granting online institution recently licensed by the state of New Hampshire that also offers auditing of their courses. There are courses taught by a range of scholars in things ranging from Old Norse to C.S. Lewis to Science Fiction.
Dr Olsen, aka "The Tolkien Professor" has a couple of long-running podcasts under his own name and Mythgard Academy.
See mythgard.org as a starting point.
Whew! That's much longer than I'd normally post! But you did ask, @freemo ;-)
@twdockery I can see why, you can really get lost in this stuff. Its so cool!