HerCurve
http://www.hercurve.com/
A spinoff from the equally excellent Sexilicious, HerCurve is an online community for lesbian, bisexual and transgendered women. A very active set of discussion forums, opinion columns, erotica, web site reviews, and much more. A place I've been known to spend far too much time...
Bisexual.org
http://www.bisexual.org
Though apparently run by a nonprofit, this site has a very commercial feel - it seems to be primarily a dating site, with connections to a couple of porn sites. But it does also have a (very small) articles section (very small as in only two articles, when I last checked), plus discussion forums and a reasonably decent resources section. They also put out BiMagazine, which I've listed separately as it's a separate site with a very different feel.
Bisexual.com
http://www.bisexual.com
Probably the biggest online community for bisexuals, with articles, discussion forums, personal ads, live chat, and more. Rather annoyingly, you have to register in order to access most of the content, and the registration process seems to assume that you're looking to place personal ads, requiring you to indicate whether you're a single or couple, for example. No way of indicating if you're in something like a poly triad, either. However, it's otherwise a good site.
Girlfriends
http://www.gfriends.com/
Highlights from the current issue, discussion forums, and online subscriptions and back issue ordering.
Good For Her
http://www.goodforher.com/
We think this is a fabulous site, but we may be a little biased because we designed it. :-) Good For Her is a women-oriented sex shop in Toronto, offering online and in-person shopping, plus workshops, an online sex advice column, and more. You can even review and rate the products in the online store!
Shamanism: Working with Animal Spirits
http://www.animalspirits.com/
I've put this here rather than under shamanism despite the title, because the focus is very specifically on animals. A very interesting site, with an appealing domain name (animalspirits.com), but slow-loading due to the many animal pictures. Over 300 animals are featured here, with photos and brief descriptions of their spiritual significance. And not just the well-known ones, either -- they've got everything from stink bugs to protozoa! One can easily get lost in here and spend hours looking up different animals, although the academic in me wishes they would cite sources for the historic/factual (as opposed to experiential) parts of the information. In the time since I first discovered it, it's expanded to include discussion boards, chat rooms, and much more. Definitely enough to earn the "Recommended Site" designation, even if parts of it are a little more new-agey than I would have liked...
Bisexual Resource Center
http://www.biresource.org/
Web site of an international non-profit organization dedicating to educating people about bisexual issues. The main page of the site is a news listing, in a blog format, but there's also a very extensive resource directory with hundreds of bi-related links.
Kama of Kingston
http://www.princesskama.com/
An interesting site by an Anglo-Indian sex worker who is working to reclaim the Devadasi tradition of Hinduism. Contains interesting views on sacred sexuality within a Hindu context.
Coalition for Positive Sexuality
http://www.positive.org/
Sex-positive sex education for teens, with information on safer sex, pregnancy, STDs, coming out gay, and more.
The Frugal Domme
http://www.frugaldomme.com/
A highly useful and entertaining site devoted to practicing BDSM on a budget. They sell inexpensive toys, and also offer a wealth of information on making your own, plus a great deal of general BDSM information, FAQs, humour, a directory of local groups, a message board, etc. A female-dominant perspective, but a lot of the information is useful to anyone regardless of gender or orientation. The site design is overly busy and thus a bit confusing, but otherwise it's an excellent site.
Feline Revolution
http://www.felinerevolution.com/
A site by two feline therians, divided into personal sites by each of them plus a combined link area. Keller's side of the site, Felinity Reclaimed, contains essays on therianthropy, spirituality, social issues and other topics; poems, and a still-nascent book review section; Kefira's side contains a few essays, some artwork, and several sections that don't yet have much in the way of content, but will hopefully grow in the future.
StarFire Rising
http://www.starkindler.org/
Probably the best intro to Wicca, in the traditional sense of the word, that you'll find anywhere on the web. The Starkindler tradition is an Alexandrian offshoot that is more overtly gay-positive than many traditionalist groups are. The site contains a considerable amount of information about Starkindler, its parent trad, and traditional Craft in general, written in a way that is straightforward and accessible but clearly geared toward a relatively intelligent and well-read visitor.
Wicca for the Rest of Us
http://wicca.timerift.net
A down-to-earth, somewhat irreverent site that positions itself as an alternative to the plethora of fluffy, new-agey Wiccan sites out there, and shoots down many popular myths and misconceptions. Enlightening and entertaining.
Body Modification E-Zine (BME)
http://www.bmezine.com/
Definitely the highest-profile body modification site around there, with a vast collection of stories and photos submitted by members of various body mod procedures from piercing and tattooing to more extreme practices. Also includes an "Ask BME" advice column, an encyclopedia of body modification related terms, and much more. Some of the more extreme content can be a little scary even to those comfortable with things like genital piercings, but those parts can easily be avoided if you're not up to dealing with them.
BiMagazine
http://www.bimagazine.org/
An online bisexual magazine with a lot of interesting articles and a very international focus, with a number of articles on the status of bisexuals in different parts of the world. Also includes poetry, visual arts and music coverage, though some of these sections still seem to be pretty sparse. The majority of the content is under non-fiction.
Desiree's Musings: The Faery Notebook
http://www.sphinxmuse.net/faery/
A subsection of a web site reviewed in the Wicca section, this site differs from a vast majority of other faery sites in that it clearly acknowledges the "darker" and less benevolent side of Faery. Contains essays on typical fairy art, stereotypical faery traits (including some ideas as to why these are associated with faery), and a collection of poetry with commentaries.
Chaos Matrix
http://www.chaosmatrix.org/
A very large and diverse collection of texts on chaos magic and related topics, including digital copies of a number of classic occult texts, a special section on occult swordplay, a wonderful occult humour section called "Banish with Laughter", and more. Probably about the largest collection of chaos information you'll find in one place anywhere on the web, and nicely designed too. Note: newly back online at a new domain, after a lengthy absence.
Nothingness.org
http://www.nothingness.org/
A large, diverse and exquisitely designed site dealing with anarchism and Situationism. Includes archives of the journal Social Anarchism, a Situationist text archive, artwork, poetry, and believe it or not, even anarchist e-cards!
The Hermetic Library
http://www.hermetic.com/
This is a huge, beautifully designed site hosting everything from the largest collection Crowley's books I've seen anywhere to Hakim Bey's works on ontological anarchy. They're also coordinating a project to put the entire library of the Golden Dawn online. Any time I start thinking my site's large, I can just take a look over here and be humbled...
Akhila's Nest
http://akhila.feralscribes.org/
A personal site on therianthropy, with essays -- often very opinionated -- fantasy artwork, etc. Very attractive design, though the "mystery meat" navigation takes a bit of getting used to. Includes a FAQ on contherianthropy -- that is, therianthropy without the experience of "shifting", where the animal self is present at all times.