YayGender.net
YayGendernet is a website created in 2009 that includes introductory materials about gender and sexuality, as well as an interactive "genderform" where users can select from identity labels to generate virtual "nametags" to display on a website of their choice.
The site's "Introduction to SGO [Sex, Gender, and Orientation]" concludes a glossary defining several non-binary terms, including genderfluid, androgyne, bigender, agender, genderqueer, and third gender.
Yay Genderformǃ
In addition to offering terms related to gender/sex/sexuality, the form allows users to identify themselves according to subcultural affinity (like "goth"), personality traits, and political views.