If ever there was an illustration as to the ultimate stupidity of DRM, this article at Techdirt comes close to perfect. The guy legally buys movies from one source, with DRM, then buys a new monitor that supports HDMI and it's associated DRM restrictions, and all of a sudden his legally purchased movies don't work any more.
The response of the companies concerned...? Downgrade to a lower-spec monitor. Duh!