At the end of Douglas Adams's Hitchhiker's Guide To The Galaxy, we learn that the Earth is nothing more than a giant computer designed to churn through the vexing question of the meaning of life. MIT quantum mechanics prof Seth Lloyd reprises this theme in Programming The Universe, arguing that the entire universe is a giant quantum computer.
But we're at page 136 before this interesting tidbit bubbles to the surface. The book's first half focuses on convincing the reader that the physical universe can be broken down into discrete bits of information and that energy, specifically the inaccessible energy of entropy... I'm getting bored just typing this.
His explanations of everything from logic gates to binary systems are technically correct, but a greater emphasis on context would have benefited these sections we have to wait until page 168 for a section entitled "So What?" For better background info on quantum mechanics and complexity theory, go straight to the source with In Search of Schrodinger's Cat, by John Gribbin, or Murray Gell-Mann's The Quark And The Jaguar.
When Lloyd starts talking about his own experiments, "massaging atoms" into states needed to create quantum computations, his writing wakes up. His enthusiasm bleeds through the pages near the end, where he muses on the way complex features of the universe arise from simple blips in the quantum world.
But just when he starts to really sing, the book ends. And there isn't even an index so you can look up the cool stuff.