No, but I've been looking into it.
I guess what held me back was, I didn't want to be a paper member-in-name-only and I was concerned that my schedule would keep me from showing up sometimes when called.
Incidentally, I don't personally know anyone who is involved either. I asked around of other riders but, as one member of a local club said, they all thought that membership was for ex-military/military only. I know from reading the site that this isn't true, but that's still seems to be the general perception.
But thanks for the post. It'll remind be to take another look.