Far in the distant, post-human future, the Cater-Zimmermann community set out to refute the theory that the universe is created exclusively for mankind by cloning themselves a thousand times over and sending each copy to a different star within the galaxy. One of the copies of Cater-Zimmermann, Paolo Venetti, arrives at Orpheus; a water-world inhabited by floating mats that perform as a Turing machine.

"The Region Between" first appeared in Galaxy back in 1970. It had originally been commissioned as one of a set of stories by different authors who all used a common starting point as set out in the story's prologue, written by Keith Laumer. Ellison's contribution was a longer work than one usually expects from him, but it nevertheless sustains its bombardment of ideas and feelings throughout. What's more, Ellison created a story that demanded a different format to allow for full expression. The result was a typesetter's nightmare but, as you will see, the experience now only makes this story all the more fascinating, it actually takes you into the story itself. Mike Ashley

When Sora's swallowship is taken out by a swarm during the war she is rescued by Merlin, a legendary man who has allegedly discovered a super-weapon built by the Way creators; a gun so powerful it I said to have stopped the previous war. Sora is sceptical, though, for Merlin has been missing for ten thousand years, yet he has not aged a day. As the current war between aliens and humans intensifies, the need to find this weapon becomes unquestionably urgent. They must find the gun before the enemy does and incinerates them. Can their quest to save humanity and end the war be achieved with Merlin's gun?

Craftsman and amateur astronomer Geoffrey Carlisle from Ely discovers that the moon is fractionally ahead of its usual elliptical orbit. He becomes instantaneously well-known for his unique observation. Using Carlisle's findings, astronomy experts discover that each star circling the moon has been slightly warped. Yet after some time, as Professor Wright from Cambridge University had predicted, the warped stars return to their rightful places, suggesting that the world is an information-ordered one, like an analogue program acting out. What then, are the actual repercussions of a computational error in reality?

'Death in the Promised Land' explores the potential dangers of becoming too closely involved in virtual reality. Parts of the story were later reworked into the novel Tea from an Empty Cup (1988), which had a sequel in Dervish is Digital (2001), both excellent examples of merging cyberpunk with the detective genre.

Here are 25 stories of science fiction that push the envelope, by the biggest names in an emerging new crop of high-tech futuristic SF - including Charles Stross, Robert Reed, Alastair Reynolds, Peter Hamilton and Neal Asher. High-tech SF has made a significant comeback in the last decade, as bestselling authors successfully blend the super-science of 'hard science fiction' with real characters in an understandable scenario. It is perhaps a reflection of how technologically controlled our world is that readers increasingly look for science fiction that considers the fates of mankind as a result of increasing scientific domination. This anthology brings together the most extreme examples of the new high-tech, far-future science fiction, pushing the limits way beyond normal boundaries. The stories include: "A Perpetual War Fought Within a Cosmic String", "A Weapon That Could Destroy the Universe", "A Machine That Detects Alternate Worlds and Creates a Choice of Christs", "An Immortal Dead Man Sent To The End of the Universe", "Murder in Virtual Reality", "A Spaceship So Large That There is An Entire Planetary System Within It", and "An Analytical Engine At The End of Time", and "Encountering the Untouchable."

Hugo Award-winning editor Gardner Dozois' annual anthology has long been considered the standard by which other best-of-the-year SF collections are judged. After two decades' worth of superlative science fiction, Dozois now presents a retrospective compilation culling from the last 20 years. Here under one banner is some of the finest work by the genre's leading authors, with a star-studded list of contributors that features among others: Stephen Baxter, Greg Bear, William Gibson, Terry Bisson, Greg Egan, Ursula K. Le Guin, Robert Reed, Robert Silverberg, Bruce Sterling , Charles Stross, Michael Swanwick, Gene Wolfe. A number of the selections are now considered classics. Some notable stories include: 'Blood Music', Greg Bear's Hugo-winning exploration of nanotechnology. 'Bears Discover Fire', Terry Bisson's tongue-in-cheek consideration of future ursine evolution. 'The Left Hand of Darkness', Ursula K. Le Guin's coming-of-age SF tale. 'The Winter Market', in which William Gibson returns to the subject that made him a cultural icon, cyberpunk. With work spanning two decades, this is the most significant science fiction short story anthology published in years.