Religion in SF/F Literature - http://www.adherents.com/lit/index_adherents.html Includes c. 2000 references to real churches, religions, and tribes in science fiction novels and short stories.
Steampunk - http://www.steampunk.com/ Portal for SFF - includes links to author websites, and direct links to online texts.
The Locus Index to Science Fiction - http://www.locusmag.com/index/ Bibliographical database of novels and short stories published after 1983. From the US trade journal for the genre.
Transformation Stories List - http://www.transformationlist.com/ Books and stories with shapeshifting (werewolves, and nanotechnology) as a theme. Searchable, with brief descriptions and reviews.
Classics of Science Fiction - http://classics.jameswallaceharris.com/ Site devoted to identifying the classic books of science fiction.
Lunacat.net - http://www.lunacat.net/books/index.htm SFF books written by women. Broken down by author and type of story.
Jewish Science Fiction and Fantasy - http://www.sfsite.com/~silverag/jewishsf.html List of SFF novels and shorter works somehow certified kosher.
Bibliography of Mormon Speculative Fiction - http://www.mormonsf.org/ Works published by or about Mormon SFF writers, including novels, short stories, articles, and interviews.
Uchronia: The Alternate History List - http://www.uchronia.net/ Annotated bibliography of novels, stories and essays involving the 'what ifs' of history.
The Moon in Science Fiction - http://www.biblioinfo.com/moon/sf_moon.html Bibliography of SF novels dealing with the moon.
Islam and Science Fiction - http://islamscifi.com/ Resource on Islam as it appears in science fiction books and cinema.