I like Steam. I don't need to keep switching disks, and in fact don't even have disks for many of my games. I can install them on unlimited number of computers, and play them anywhere. Unfortunately, ALWAYS having an internet connection is not always possible for everyone. So why not have something like Microsoft has... one time phone activation. You provide your key, their computer checks to make sure you are the legit owner of that key, then you type in some numbers,... voila, you are activated. DRM that messes with your boot sector, causes lockups, is seen by your antivirus software as a trojan and crashes your system, are all ways to totally alienate your customers. Unobtrusive DRM is the way to go.