Read the Docs has been hosting open source documentation for over four years. We've spent our time at PIE building a product for businesses. It works the same as our open source site, but with added features for businesses. In fact, we even support Markdown now :)
If you want to play with the tech for your OSS project, check out https://readthedocs.org Please let me know if you have any more questions about PIE or Read the Docs. We're announcing our private beta today, and invites will start going out soon.
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