The FBI Database - Excellent episode guide and fact achives plus games, insider info, and merchandise.
The X-Files Alphabet Book - A-Z info about the X-Files, from Gillian Anderson to Zeta Recuilli (a race of aliens). If you need to know it, it's here.
#X-Files Headquarters - Message boards, live chat, and info about the show and the actors.
BRAWS - Broad Reform Advocates For Walter Skinner - An "online cult/activist group of X-Philes" trying to increase the role of Assistant Director Skinner. The wackos are out there.
Cancerman's Lungs - An interesting perspective on The X-Files through the eyes of the one and only Cancerman.
Complete X-Files - Long list of links including screensavers, images and sounds, interviews, episode guides, cast info, and lots more.
Dith's X-Files Reviews/Previews - Reviews and previews of each and every X-Files episode. Also includes a small supply of links.
The File X Cabinet - The Science Facts Behind the X-Files - Info about the "science" (or lack thereof) behind the X-Files. Included are synopses, links, and scientific explanations.
Inside the X - Summaries of X-Files episodes, along with commentary, pics, sound and video files, and the chance to buy each episode on video.
The Mulder/Krycek Romantics Association - Want to see Mulder and Krycek walk off into the sunset together? Be with like minds at the MKRA site.
The Netpicker's Guide to The X-Files - "The Guide" to the blunders and errors made, found by X fans. Includes faulty logic, continuity errors, scientific boo boos, and more.
Songs in the Key of X - Music from the X-Files.
To the X - X-Files and related readings, shockwave interaction, and links.
The Truth Is Out There - X-Files episode info, fan groups, images, merchandise, and links.
The Well-manicured Man - An impressive amount of fairly well-organized links to everything X-Files, including but not limited to W-M Man.
X-Files (rutgers) - R.U. a fan? Go here for links and FAQs put together by devoted Rutgers University X-Philes.
The X-Files - Official Site - Official FOX site.
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The X-Files Corner - X-Files info for native Canadians (where TXF is shot, in case you didn't know).
The X-Files Episode Guide - Quick but thorough descriptions and summaries from every episode thus far. Includes noteworthy quotes from most episodes.
The X-Files U.K. - The usual X-Files fan stuff, including guides, links, pics, etc.
X-Filing Cabinet - The usual files, including character bios, actor bios, lots o'links, pics, and the like.
The X-Fools - "The spoof is out there."