The Science Fiction and Fantasy SIG (Special Interest Group) of American Mensa has been in existence since 1976. The group's publication is the InterdiMensional Journal, which costs $10.00 for 8 issues ($16.00 in US funds if you are outside of the USA). Mensa membership is not required to subscribe to the Journal or participate in the SIG.
The InterdiMensional Journal is loaded with book, movie, and television reviews, artwork, poems, and short stories. It's just a lot of fun, and you really can't beat the price.
Although no actual "test" is needed to join, the administrator and I agreed that a screening process would be wise. In this vein, I have concocted a quick analogy puzzle. Solve it, and you will be taken to the main page that gives full contact information for the group.
Simply replace "theanswer" in the URL below with the actual answer (use all lowercase letters), paste it into your broswer, and hit "enter". If you have the correct answer, you'll be taken to a page that says "Science Fiction and Fantasy SIG" at the top. Answer it incorrectly, and you'll find yourself at the main page of Puzz.com, or on another of our pages. Feel free to try as often as you like: