DRM is ghey. I don't dissagree with copy protection - developers have a right to protect their intellectual property, but I seriously dislike vendors sneakily installing stuff behind my back. They're as bad as spyware authors sometimes. Just look at the Sony debacle!

I believe Autodesk have a scheme in action similar to what Dave's talking about. Limited time licencing is a great idea, and should hopefully become the way the future for large software packages like Logic Audio and Pro Tools. The system encourages people to pay for software by reducing the apprehention to purchace a piece of software just to evaluate it. Otherwise you'll be like most people (including myself on occation I have to admit) and just pirate it.