The 3rd Edition of the mighty Encyclopedia of Science Fiction has gone live. The previous two editions of the encyclopedia were massive print books large enough to demolish buildings, but the third edition is twice the size of either and hence will only (so far) be available on the Internet.
This is the so-called 'beta release', consisting of roughly 75% of the text of the full book. The remainder of the text will be released over the next year or so, with regular updates appearing afterwards.
A quick look through the encyclopedia suggests this is a monumental, massive addition to the canon of SF reference works, likely to supplant its predecessor as the definitive guide to the genre and possibly likely to supplant TVTropes as the website you go to check out one article and end up spending an afternoon there :-)