This is why I'd like to see copyright law changed to the following model:
1. The creator of a copyrightable work is granted sole reproduction rights to their work indefinitely.
2. The creator may only hold copyright to one of each class of copyrightable work at a given time (book, musical album, movie, etc). Previous copyrighted works are surrendered into the public domain upon the publishing of a new work that is itself not released directly into the public domain.
3. All copyrights expire five(5) years after the creator's death.
This system allows a creator to collect money from a work for as long as it remains profitable to do so. However, being able to possess only one copyright at any given time removes the incentive to create and then retire for life. With unlimited (in number) copyrights, a creator could create several works and collect a massive amount of cash. Limiting it to one at a time ensures that as soon the popularity for that work declines below an acceptable threshold, the creator would need to create a new work in order to maintain a certain level of income. If the creator happens to create something so profound that it remains highly profitable for many years they should be allowed to kick back and reap the rewards; if it is really that valuable to society it only seems fair. Clause three just helps ensure that copyrighted works are innevitably released into the public domain, after a time period sufficient for contributing to the creator's estate. I.E. The creator could will his copyright to an heir allowing the heir to collect on it for five years, which would be held separate from the heir's own copyright count (if they indeed hold any at all.) Considering you'd actually have to die to pass that copyright to someone else, it would be very costly to abuse (especially considering you could get more than five years out of it if you simply stayed alive.)
The current system, as you say, is attrocious/an attrocity. It is robbing society of works originally promised to them simply by exptending copyright, and allowing 'ageless' corporations to hold copyrights, rather than people. The system is broken, and I feel mine is about as simple and as fair as one could conceive. I welcome anyone to poke holes in it however, I enjoy (constructive) criticism.