The traditional and ubiquitous digital computer has changed the world by processing series of binary ones and zeroes.very fast. Like the sideshow juggler spinning plates on billiard cues, the classical computer moves fast enough to keep the plates from falling off. As computers become faster and faster, more and more plates are being added to more and more cues. Imagine, then, a computer in which speed is increased not because it runs faster, but because it has a limitless army of different jugglers, one for each billiard cue. Imagine the quantum computer. Julian Brown's record of the quest for the Holy Grail of computing -- a computer that could, in theory, take seconds to perform calculations that would take today's fastest supercomputers longer than the age of the universe -- is an extraordinary tale, populated by a remarkable cast of characters, including David Deutsch of Oxford University, who first announced the possibility of computation in the Alice-in-Wonderland world of quantum mechanics; Ed Fredkin, who developed a new kind of logic gate as a true step toward universal computation; and the legendary Richard Feynm.