Perfect example of why all DRM is doomed to failure. My laptop is having a hardware problem, so I pop the hard drive from it and swap it out with another, identical machine here at work. Put laptop in docking station, fire it up...and iTunes wakes up, tells me that this machine is not authorized to play my iTunes "purchases" (including free downloads from the iTunes store), and promptly removes them from my iPod.
Think about that. The poor iPod was simply connected to the wrong place at the wrong time. I didn't change iPods. I didn't even technically change computers, since I took my harddrive, my install of iTunes, all that stuff with me. Any library that I had on that machine was still there. But it sensed that I had changed machines and because, and this is a direct quote, "you are not authorized to play them on this computer", it removed them from my iPod. They are still on my computer, and I can play them if I want to authorize this machine, which I don't, because it is a loaner and it would be a waste. But I don't see how Apple figures they had a right to delete stuff from my iPod? Why not let me keep playing them on the iPod and simply tell me I can't play them on the computer?
All DRM is evil and bad for the consumer. It prevents you from using products you purchased in ways that you should legitimately be allowed to use them. Never forget that.