These two books by Daniel Suarez are the finest computer-takes-over-the-world books I have ever read. Suarez is a computer consultant and his material is relentlessly factual; when he describes how a server gets hacked, it's 100% accurate.

Computer gaming genius Matthew Sobol has just died, but he left behind him a gaming engine that can do more than just fight opponents in a MMORPG. It is also a distributed botnet, capable of hacking its way into servers everywhere and spreading beyond all chance of eradication. And Sobol has left it with an agenda: the overthrow of corrupt western establishments. The power of the botnet - or 'Daemon' - is evident when it successfully defends an uninhabited house against a infiltration team and engineers the conviction and execution of the detective investigating the murders it has caused.

This is superbly written gripping stuff from a master story teller. My only peeve is that they are clearly the first two-thirds of a trilogy and yet I haven't seen any mention of a third book yet.