Here is a list of various website of value in no particular order:
The Fire Kasina is a website by Duncan Barford, Florian Weps and Daniel Ingram about the fire kasina and about a 12-day retreat they did practicing it. Shannon Stein has added her audio diaries to it, which are highly recommended.
Interactive Buddha - The creator of this site's homepage. His book, Mastering the Core Teachings of the Buddha, can be found there as well as an assortment of other useful articles. Those seeking to understand a lot of the model terminology used on this site should probably check it out. It also contains a lot of good advice on such topics as the Dark Night, realistic models of enlightenment, helpful instructions for practice, and other practical topics.
Kenneth Folk's dharma site, often referred to as KFD, is an early spinoff and current sister site of the DhO and contains a lot of crossover membership. It got shut down on WetPaint for unknown reasons but is now found here. However, a new public version is now back up and running and found here.
The Dharma Underground spawned the Dharma Overground, which spawned KFD and OE when the first Great Schism occurred, and then KFD had its own series of schisms, one of which spawned The Dharma Forum Refugee Camp whose members include some of the early DhO members, and that spawnened the grand attempt at re-integrating some of the fractured communities called awakenetwork.org.
DialecticalAmy is the blog and website of Amy Donohue on practice and this post-post-modern life.
Alan Chapman has a current project called I Am Fountainhead. The Baptist's Head and Occult Experiments in the home appear to have vanished. Something along similar lines can be found at Occult Corpus.
Inspired by The Baptists Head is a magickal and practice forum called Salome's Revenge, created by dharmandy with some help from Ona Kiser (whose personal sites are www.onakiser.com and A Little Death). Offering workshops and dharma teachings is Wild Presence, including Karen Gifford at www.karengifford.org, who trained with Alan.
The Hamilton Project is another site dedicated to practical dharma that spun off of the DhO and KFD.
Deconstructing Yourself is the site of Michael Taft and Jessica Graham and is dedicated to awakening and wisdom.
Deep Mindfulness Collective is the mentoring project of Rakhel and Janusz and is strongly influenced by Shinzen Young and other teachers.
Inward Bound Mindfulness Education (iBme) helps train teens in mindful living and runs retreats for teens. Some great people work there.
There is a Reddit group dedicated to pragmatic dharma and high-level discussions.
Ruthless Truth is the website of the Direct Pointing movement, an immediate form of inquiry into No-Self, and a group of them (some of whom have been on the DhO) split off and formed Liberation Unleashed.
Shinzen Young is a meditation teacher who was a friend of Bill Hamilton and teaches a modernized version of vipassana mixed with influences of Zen and Vajrayana. Har-Prakash Khalsa does videos of Shinzen and also teaches meditation and does his own videos and art.
DharmaTreasure is the website of Upasaka Culadasa (aka Dr. John Yates), a Tibetan and Theravadan teacher who is interested in a modern, scientific take on ancient wisdom.
The Integral Dharma Institute is the dharma resource site run by Andrew Olendzki, an accomplished scholar of the dharma.
DharmaFarers has a lot of textual resources and things in translation.
http://hokai.info/ is the website of Hokai Sobol, a very skilled Vajrayana practitioner and scholar that was part of the core group that began at the DhO.
Basiscrunch is a website about no-self that adds a scientific and plain-language perspective.
10% Happier is the journalistic meditation promotion project of the ever-personable and inquisitive Dan Harris of ABC News.
Post-Traditional Buddhism is a thoughtful, intelligent blog dediated to rational critique of current emerging Buddhism. It is also living proof that non-toxic things can actually arise from the speculative non-buddhist movement despite themselves, and is the home of the Imperfect Buddhist Podcast.
Kamalashila teaches meditation in the London area with Triratna.
Andrew Olendzki is a Buddhist practitioner-scholar who has been kind enough to post some of his helpful maps, tables and the like on his website.
http://www.constancecasey.com is Constance Casey's site.
robertthanattarigpa.blogspot.com/ is the blog of Robert Thomas Hindmarch.
theheropass.blogspot.com/ is a link to the blog of a 20-year old who claims stream entry.
www.vincenthorn.com/ is a link to the blog of an ex-DhO member and yet one of the core founders, Vince Horn. His current meditation teaching project with his co-teacher and partner Emily Horn is Meditate.io which is home to Mindfulness++, a revamping of meditation for the digital age.
Leigh Brasington's Jhanas Page - A great collection of articles and information on the jhanas, created and assembled by jhana teacher Leigh Brasington.
Cyborg Buddha Project - The Cyborg Buddha Project was founded to "promote discussion of the impact that neuroscience and emerging neurotechnologies will have on happiness, spirituality, cognitive liberty, moral behavior and the exploration of meditational and ecstatic states of mind."
Spirituality Explained is the work of Frank Heine and an attempt to integrate neurobiology and meditative perceptual models.
Coffee with Pierre & the Philosophical Community
Bhikkhu's Blog - A Canadian born Theravada monk ordained in Thailand in 1992. Abbot of the Arrow River Forest Hermitage.
Access to Insight: Readings in Theravada Buddhism - translated scriptures from the Pali Cannon and links for Theravada practitioners
Tai Chi Methods
The Tao Bums - Website about Taoism, but i have found more great Buddhist related information, including links to Daniel's information, than any other site. Lots of very bright people from different backgrounds, countries, knowledge bases.
Bardo Comix - This is one of the best links I've found in a while--an online comic book summarizing the Tibetan Book of the Dead
Vipassana Fellowship - has great resources, including (at a glance) much of the Pali canon in HTML and Mindfulness in Plain English (Complete text in HTML)
BuddhaNet's eBook Library - contains many great books for download, such as Mahasi Sayadaw's Practical Insight Meditation and Thanissaro's Wings To Awakening (far too many titles to list here)
Buddhist Publication Society - Offers many great books by both western and eastern masters of the practice. Also has past newsletters available for download.
Practical Insight Meditation - may be found here, and for those who want print versions of this and many other related books: http://www.bps.lk/meditation.asp
In This Very Life - (Online version) by Sayadaw U Pandita, also On The Path to Freedom (.pdf version)
American Buddha Online Library
Forgotten Books has a nice section of old and unusual Buddhist books online for free.
BuddhaDust - Some unusual Sutta translations
Tricycle is a classic magazine about Buddhism.
What is Enlightenment?
Yoga Sutras Patanjali - An ocean of commentary and articles on the yoga sutras (and some other topics)
Buddha Net - Great eBook collection
The Bodhisattva Ideal in the Theravada: an eye-opening article for those who think that the bodhisattva ideal is purely a Mahayana doctrine.
Buddhist Geeks - A free Buddhist podcast with interviews and dialogues with various western Buddhist teachers, scholars, and practitioners. Created and hosted by members of the Dharma Overground, as well as having several interviews with other members (including Daniel Ingram & Hokai Sobol) this podcast has a variety of good audio content on various topics and at different levels of depth.
Audio Dharma - "This site is an archive of Dharma talks given by Gil Fronsdal and various guest speakers at the Insight Meditation Center since 2000. Each talk illuminates aspects of the Buddha's teachings. The purpose is the same that the Buddha had for his teachings, to guide us toward the end of suffering and the attainment of freedom."
Dharma Talks by Ajahn Sumedho - I found Luang por Sumedho's teachings very accessible, here is a page of his Dhamma Talks. Some of the links might not currently work.
Birken Forest Monastery : 3000+ Dhamma Talks Download Page - this page has english talks from Ajahn's (mostly from Ajahn Chah's lineage; Thai Forest) from around the world
Jill Bolte Taylor: My Stroke Of Insight - A neuroscientist talks about how she experiences enlightenment during a stroke (and theories about what brain functions are related to that).
Collision with the Infinite - A great book review of Suzanne Segal's book. "As she stepped into a bus on a street in Paris, an unexpected mental cataclysm split her consciousness in two. A few months later, her sense of personal self disappeared forever."
DIY Dharma - exhaustive amount of audio, but poorly coded page taking a long time to load
Dharma Seed - has a truly massive compendium of free dharma talks (mp3 or streaming) by pretty much all of the mainstream Western Insight teachers
Suan Mokh (Ven. Ajahn Buddhadasa)
NM Center for Meditative Inquiry and Retreat - Operated by Jay Cutts, this Center in northern New Mexico is for people from any meditation traditions (Tibetan, Zen, Vipassana, Hindu, Western) or no tradition at all, as well as for people interested in teachers such as Pema Chodron, Toni Packer, Thich Nhat Hanh, and Krishnamurti. Jay studied with Toni Packer for many years. Explore more deeply what meditative work is and how it sheds light on the concerns of our lives, not theoretically, but from a quiet listening that includes others and oneself.
Antaiji: Temple of Peace - website of the largest soto-Zen temple in Japan
Ven Ajahn Maha Boowa
Ven. Nanavira Thera Dhamma Page
Opening Mind - In 1982, the Son (Zen) Master Chong-An (who later was given the name Myo Bong) of the Chogye Buddhist order of Korea, suggested the creation of a center that would combine Buddhism and Platonic Philosophy. As a result, a short while later in the Spring of '83, Pierre started the Opening Mind Academy as part of his Virtue Mountain Temple in Huntington Beach, CA for the training of Philosphical Midwifery, the exploration and study of dreams, and reviewing problems which students experienced in meditation.
Franklin Merrell-Wolff (here and here) - The writings of the American spiritual philosopher and Realizer, Franklin Merrell-Wolff (1887-1985), are deep, difficult and profound. His 3 books are classics among those with the insight to grasp their meaning. FMW was trained in mathematics, philosophy and psychology at Harvard. He abandoned a promising academic career and devoted 20 years to the pursuit of Enlightenment before realizing success. Because FMW is so difficult, not many people read him. Because his Realization is true, and he expressed it in precise, logical Western terms, many people should.
Puppetji - Puppetji is a guru/muppet who speaks his "wizdumb" on Youtube. Useful for periodic reminders not to take oneself so seriously.