Most of us have books that we've never read. We buy them, then put them away for a rainy day. The problem is that by doing that, we usually avoid buying that author's next book until we actually get around to reading the first one. To force us to get cracking, an Argentinean publisher is printing books using disappearing ink that starts to fade after just a couple of months.
The book is an anthology of new Latin authors, just the people who really want you to read their work, so you will move on to their next project. Publisher Eterna Cadencia ships the book in an airtight wrapper, and it's only once you break the seal and expose the pages to air and light that the clock starts ticking.
If only they had had this technology for text books when I was in school, I might have spent a little less time procrastinating and more time studying.