I read this is nearly a single sitting - it is that good. Think Nick Twisp as a hacker, and you come pretty close. But more important, this is a must-read for anyone under the age of 25 (you'll know why I say "25" when you read it) concerned with the abundance of surveillance tracking nearly every move, and how quickly surveillance and data-mining can turn into full-scale repression. 
 The book begins with ordinary surveillance devices that most kids confront, creating the high school panopticon of rent-a-cops, clear plastic backpacks, hall passes, and school-wired computers. Combine this with FasTrack, Clipper/Translink, and ordinary credit card usage, and you get a pretty sustained framework for distinguishing "normal" from "deviant" behavior, once the Bayesian equations are better worked out to rid the system of noise.* It is not such a leap to go from that to gait-recognition devices and the propaganda necessary to sustain them. And then throw in a "state-of-emergency" event, and watch the civil liberties crumble. This isn't science fiction, after all; it is simply a description of the last ten years we've lived through. 
 Within the context of a well-written story of a youth attempting to defeat the madness of his circumstances (again, this is the Nick Twisp connection), Cory Doctorow teaches readers about the logic of surveillance and the techniques that are used both in its service and in resistance to it. Hacking the Xbox is real; basic cryptology is explained. (I kind of wish that Marcus, the main character, had mentioned reading Neal Stephenson's Cryptonomicon, but I'm happy enough with the Kerouac moments). 
 With the Wikileaks cables now being released on a daily basis, this book is extremely timely. It helps readers to make the distinction between "secure" and "private." As Bruce Schneir writes in an Afterword, "Secrecy and security aren't the same, even though it might seem that way. Only bad security relies on secrecy; good security works even if all the details of it are public." The U.S. government, and the cabal of national governments across the globe, have fooled us into thinking we are more secure the less anyone knows. And Wikileaks is trying to wake us up. 
 * One other point. There is an amazing description of the mathematics behind "finding terrorists" based on a tracking system that is even 99% accurate, a system that will identify tens of thousands of people as "terrorist" even if there are ten or twelve actual terrorists around. Read this book. Read and remember these simple equations. And then think about your last trip through an airport.