There is one definite use for this: technical books. I had a clear-out recently and got rid of books on obsolete products. They were literally worthless - you can't even buy e.g. Oracle 7 now, even if you wanted to, or download it, so I couldn't donate them to a school or something. But all in all, what I threw out probably cost well north of a grand, new.
Those are the 'current' books I wrote about. I think keeping the knowledge in them is likely a good idea, somehow or another, but see no compelling reason to keep physical copies of them.
