Ghost In The Shell - Stand Alone Complex Volume 1: The Lost Memory, by Junichi Fujisaku
I've been watching the Ghost in the Shell anime on Adult Swim lately and enjoying it quite a bit. I know it's originally a manga, but I've never been able to get in to those. But there's at least a couple actual books set in that universe and this is the first one.
The world they're set in has a very Matrix feel to it (I think the Matrix guys used GitS as one of their inspirations so that makes sense), the main character is essentially a brain inside an artificial body. Just about everyone is hooked up to a version of the internet, and people can be "hacked" though it.
It's a Japanese series so there's a lot of subtle differences in cultural priorities, what's acceptable behavior, what a person's goal in life should be... it's really interesting.
The story in this one has to do with teenagers that are becoming terrorists without any warning.