It boggles my mind that the copyright system in the US (and much of the world for that matter) has reached the state that it's in now. It's really rather depressing when you think about it. I look at my movie collection and I find a large number of grey market discs for movies and tv shows that either haven't made it to the US yet and/or are priced ridiculously high in their region 1 format. I look at my book collection and I find a fair number of books that are out of print and can't be enjoyed by people at large.
I also thought about the 4 or 5 different versions of movies which seem to be getting released with depressing regularity (theatrical version, extended version, unrated version, super-special director's cut version, airline version, etc...) in a fairly transparent effort to double dip and get the die hard fans to buy multiple copies of essentially the same movie.
Then I got to thinking about old movies, music, and books that end up orphaned because their copyright holder is hard to track down or just doesn't care about them. I thought back to some of the RIAA debacles of years past where the record labels actually claimed that they didn't know exactly what they owned, but they knew it was a lot.
Then I thought about a way to if not fix the copyright mess, at least make it more friendly to us, the consumers.
Instead of just granting an exclusive copyright for a creative work, a commercial copyright should also entail a responsibility to keep that work available to the public (at least in a digital format) for the duration of the copyright. In this day and age, what copyrighted material couldn't be preserved digitally in some form? Books could become PDF files, CDs and DVDs could be archived on hard drives, photographs could be stored digitally, etc... For however long someone was granted a commercial copyright and wanted to maintain it (and especially when corporations like Disney lobbied to extend their copyrights long after the original creators' deaths) they would be responsible for making that copyrighted work available to people in some reasonable/current format and it would have to be available for sale at a reasonable price (i.e. a digital copy of a book, CD, movie, photograph couldn't cost $1,000 dollars... especially if it was only provided as a download, i.e. no physical media).
Copyright would still have an upper limit, but if an an individual or corporation decided to release something into the public domain they could notify something like the Library of Congress (which should also at least have digital copies of the copyrighted work) and they'd be off the hook for providing it to the public. They might also need to renew their copyright (just like we renew our driver's licenses) every 5 or 10 years (a period of time short enough so that if a company dissolved or an individual died there would still be a good chance of retrieving their work if necessary) up to the maximum allowed and failure to do so could serve as an implied release into the public domain. At that point the LoC could handle the distribution and availability aspect of the law and people would be charged a reasonable maintenance fee (i.e. something that would help cover bandwidth, storage (digital or physical) and general archival/retrieval expenses).
While this might seem a bit hard for small bands or authors, I think it could be designed to be easy enough that anyone could maintain their copyright interest without too much difficulty. If the LoC was the de facto storage repository for all copyrighted works, a copyright holder wouldn't even need to keep copies of their work around. They could easily obtain a copy of their works from the LoC and resell them to someone who inquired about it with a reasonable markup (as a copyright holder it would be their right after all).
Ultimately, it seems that if a copyright is something that benefits the entity that owns it then it would seem only fair that they should have some responsibilities associated with that right/benefit and being required to be capable of providing a copy of their works (at a profit) to the public seems like a reasonable obligation to someone who can restrict who can or cannot make copies of their work.
 - It occurs to me there should be a distinction between a commercial and private copyright. Your home movies, vacations photos etc... would have a private copyright which would be exempt from having to provide copies to the public. Perhaps even small commercial ventures could be exempt, but once they reached a certain point or scale the change in copyright would come into effect (e.g. someone in a garage band selling CDs, or a small/private photographer could be exempt, but MGM, Sony, Random House etc... shouldn't). Maybe calling it corporate copyrights or commodity copyrights would make more sense. I'm not sure about exactly where the division should be, but I think the general idea is clear, something that's a one of a kind or one of a very small number would be treated one way, something that's produced as a commodity item couldn't arbitrarily be removed from the market at the whim of it's copyright holder.