One downside of paper books is that through normal use they tend to grow old and die. I even have a small collection of books which I don't dare touch because they'd fall apart. Impermanence is a known fact, but have you ever thought of what would happen if a publisher used that as a way to drive book sales?
I just found one, and it's rather interesting., a publisher based in Argentina, has recently a new book called The Book That Can't Wait. This book is an anthology featuring excerpts and short works from a number of new Latin American authors, but the most important detail about this book is that it is printed with disappearing ink.
The ink oxidizes and disappears within 2 months of being exposed to air. This of course means that the book needs to be sold in a sealed bag. but more importantly it forces the new owner to read the book in a timely fashion. Clever, no?
I have a to be read pile which is a threat to low -resource servers, so I can appreciate what they're trying to do. If I had bought this book I might have left it sitting for months before cracking it open, and with the disappearing ink that's simply not a viable strategy.