Whoa, this list got huge! Good to see it back, Mhaeric.
I've just started my Linkshell, which will hopefully expand to a Free Company in the near future. It is not specifically a GSSM group, but I defer to you whether you want to list it under friendly or anti-discrimination.
"Gamut" on Balmung
Website:
http://gamutgaminggroup.net/
A quote from our FAQ, which I think is the most pertinent to this thread:
"Q. Is Gamut an LGBTQ group?
A. No. Part of the basic philosophy behind Gamut is that respect and decency should not be reserved for 'special interest' groups, but should be a given in any community. As such, Gamut choses its members not by some specific attribute, but by the quality of their interaction with others. After all, even when a person belongs to an oppressed group, that person may still be oppressive or rude to people of other groups. However, through the very nature of its philosophy, Gamut is definitely welcoming to many gamers who do not feel welcomed or safe in most 'mainstream' gaming groups, including queer folks."