Because someone asked, and I aim to please, I just added a message board.
I did not spend much time looking for one; I am using free software from Aimoo. It looks like it has the features that people want in message boards. It seems customizable, although I cannot figure out how to turn off its sound, which might get very irritating after a while.
You would have to sign up for it. It also supports messaging between members, including private messages. It also supports a chat room although that is not up yet (supposedly tomorrow.) I don't know if there are enough people here to keep this interesting; we will see.
I really don't want to spend much time moderating it, but it might be a useful place for people to have side discussions or to place reference materials.
If it looks like it is being abused, or of it is more effort to maintain than it is worth, I'll simply delete it. So don't get too attached to it yet!
You can see a link to it on my left sidebar under "Pages."
Check it out.