Hanford Lemoore points out that not all DRM is bad. Specifically, takes the position that DRM for trial software (try-before-you-buy) is good.  I’ll have to admit that until now I’ve been vehemently opposed to all DRM. I had not even considered the TBYB model.
Most software trial versions I’ve used did not have DRM, but were crippled in various ways compared to the full (paid) version. For instance, in engineering or design software, saving or printing might be disabled. In a game, only a subset of the levels might be present.
If I could use the full featured version of software for a trial, by agreeing to accept the DRM and abide by the license restrictions, I would have no complaint, provided that if and when I choose to buy the software, it is not encumbered by DRM.
The general reasons I oppose DRM is that it makes the product less useful to me, or even completely useless. For instance, the DRM on video discs (DVD, HD-DVD, Blu-Ray, etc) makes it very difficult to watch the video on a computer running Free Software. While preventing people from watching DVDs on Linux was probably not a specific objective of the studios, it has that effect. Even in cases where people have reverse-engineered the DRM to make it possible to play the media with Free Software, laws such as the US DMCA may make it a criminal offense to perform that reverse engineering or distribute the resulting software. This is one reason why most Linux distributions are not able to include DVD player software.
Interesting viewpoint: not all DRM is bad
Hanford Lemoore points out that not all DRM is bad. Specifically, takes the position that DRM for trial software (try-before-you-buy) is good.  I’ll have to admit that until now I’ve been vehemently opposed to all DRM. I had not even considered the TBYB model.
Most software trial versions I’ve used did not have DRM, but were crippled in various ways compared to the full (paid) version. For instance, in engineering or design software, saving or printing might be disabled. In a game, only a subset of the levels might be present.
If I could use the full featured version of software for a trial, by agreeing to accept the DRM and abide by the license restrictions, I would have no complaint, provided that if and when I choose to buy the software, it is not encumbered by DRM.
The general reasons I oppose DRM is that it makes the product less useful to me, or even completely useless. For instance, the DRM on video discs (DVD, HD-DVD, Blu-Ray, etc) makes it very difficult to watch the video on a computer running Free Software. While preventing people from watching DVDs on Linux was probably not a specific objective of the studios, it has that effect. Even in cases where people have reverse-engineered the DRM to make it possible to play the media with Free Software, laws such as the US DMCA may make it a criminal offense to perform that reverse engineering or distribute the resulting software. This is one reason why most Linux distributions are not able to include DVD player software.