I want to highlight a recent series of posts on AACS (the copy protection scheme used by HD-DVD and Blu-ray). They start with an overview of how the system works, describe which piece was recently cracked, and then devote some entries to the cat and mouse game between the crackers (who want to keep the authorities from knowing which software they had cracked, as the authorities can then disable that software's key in future releases) and the authorities (who have designed the system such that they can track down exactly these people -- the sixth post describes some of the design decisions they've made to facilitate this). They eventually build up to an economic model predicting the behavior of a smart attacker and what that bodes for AACS in the future.
This post is the most recent in the series, but it has links to the previous ones so you can read them in order. Good stuff.