The Children of the Sky is the third novel in Vernor Vinge's Zones of Thought cycle of novels, three brick-sized, Hugo-award winning novels that are the near-perfect balance of science fiction's twin traditions of wild speculation and high-intensity storytelling.
A summary of Children's plot: Imagine bootstrapping a fallen civilization into transcendance using nothing but a collection of hive-mind Machiavellis, a crippled hyperadvanced space-ship, and a pack of surly, scheming orphaned adolescents. Oh, and then there's the vengeful god ramscooping itself to relativistic speeds a mere 30 lightyears away.
That gives you an idea of just how far-out and far-ahead Vinge is thinking. The story revolves around the refugees from a crashed spaceship — the children of a hubristic human colony that had edged up to the border of the galaxy's transcendent zone, where hyperadvanced beings can manipulate the very laws of physics. These Icaruses had hoped to raid the gods' archives and find a shortcut to their own godhood, but instead they woke a monster, one that chased them to a distant world and nearly killed them. But they were saved by a hero who twisted the laws of physics and sent the Blighter Fleet (as the monster was called) thirty lightyears away in the blink of an eye, and died in the process.
Ravna Bergsndot survived the armageddon, and it was she who woke the orphaned children from their coldsleep caskets, and, with them, set about rebuilding a civilization advanced enough to turn back the Blighter again, racing to bring her exile-world from medieval fiefdoms to physics-bending demigods in a mere century.
In this, the humans are aided by the Tines, a race of doglike hive-intelligences. Three or more Tines come together and form a collective consciousness, synchronizing with high-speed, ultrasonic chirps. A literal society of minds, the Tines are essentially immortal — they need merely replace injured or killed individuals with new members. But the Tines are sorely limited in ways as well: if two Tines get to close to one another, their "mindsounds" will mingle, and their consciousness dissolve. Adding new Tines to a pack-individual can change its identity, sometimes creating new and unrecognizable packs.
Even with the Tines' ingenuity, Ravna's quest would be hopeless, except that she is able to avail herself of the libraries of the Out of Band II — the crashed starship that brought them to the Tines' world — and its endless archive recording other civilizations that had bootstrapped themselves out of similar situations. With the Oobii, this should be nothing more than a serious engineering challenge.
But even the children of near demigods are not immune to human frailty and scheming. And the Tines are hardly universally benevolent. What starts out as a fascinating thought-exercise in how you could combine knowledge, computation and raw materials to make an advanced civilization out of stone-age conditions quickly turns into a fabulous novel of intrigue and politics, as crosses, double-crosses and triple-crosses pit Tines and humans against one another in a quest for power, dominance, and vengeance.
Vinge's explosive imagination and deft storytelling make epics zip past like hummingbirds — you'll steal daytime moments to read more, and lie awake at night contemplating what you've read. Vinge is best known for the mind-bending ideas that his science fiction delivers like a warhead (he came up with the notion of the "Singularity," among other things), but the missile is as well-engineered as its payload: Children is an adventure story with teeth, mindbending technical speculation blended with graceful storytelling.
This is the third (and not the concluding) volume in the cycle. The first two are A Fire Upon the Deep and A Deepness in the Sky. Theoretically, you could follow Children's plot well enough without the benefit of the first two, but they are such treats themselves, you'd be depriving yourself if you did.