Daemon by Daniel Suarez

The ideas in this book are so creative, fresh and insightful that it puts this book in a class of it's own. The story is pretty good too. PW: Gaming genius Matthew Sobol, the 34-year-old head of CyberStorm Entertainment, has just died of brain cancer, but death doesn't stop him from initiating an all-out Internet war against humanity. When the authorities investigate Sobol's mansion in Thousand Oaks, Calif., they find themselves under attack from his empty house, aided by an unmanned Hummer that tears into the cops with staggering ferocity. Sobol's weapon is a daemon, a kind of computer process that not only has taken over many of the world's computer systems but also enlists the help of superintelligent human henchmen willing to carry out his diabolical plan.