I haven't written about DRM for ages, mainly because most people have come to agree with the proposition that making digital files non copyable is like making water not wet, i.e. fundamentally trying to change the basic properties of the thing.
Ubisoft got all creative recently, and in the game Assassins Creed 2 they implemented a scheme where the game DRM has to be continuously connected to the Internet, and the the servers, or the game exits what it is doing, taking your progress with it.
Supposedly hack proof the DRM was busted on the first day of release. (That's a fail, in my book.)
Then some naughty Internet type persons launch a DDoS (Distributed Denial of Service attack) on the DRM servers. Result? People who had legitimate copies of the game could not play it, whereas, those who had cracked copies presumably could.
Way to go Ubisoft, make sure the paying customer gets less value than the pirate. Good business model eh?