It’s pure speculation so far, but it seems that Sony might be planning to prevent gamers from running pre-owned games. Yep, it’s a DRM story again, albeit one based on interpreting a patent that may or may not refer to games (it might refer to movies on Blu-Ray). However, if it does refer to games, The Inquirer says:

While many are aware of the double profit companies make on pre-owned games, this would ensure the death of trading games between friends and even going to a friend’s house to play a little multiplayer.

Sony wouldn’t be that stupid. Would it?