I just learned about a beautiful machine called the Espresso Book Machine from On Demand Books. It is a machine that can be used in a bookstore/library to print ... well, a book on demand.
Perhaps it is because I have such a vested interest in books, or maybe it is the geek in me that loves technology, but the video is mesmerizing:
I know this sounds idiotic, however, I imagine a future where someone has purchased their ebook from wherever they do (Apple's iBookstore, Amazon's Kindle, B&N's Nook, whatever) and they decide they loved that book so much that they want to actually have a physical copy on hand. Something they can easily touch and feel. Something that doesn't require batteries, and can be read at all points of an airplane trip, not just when the flight attendants announce it is okay. Something a person can lend to a friend should they wish too. All they have to pay for is the cost of the materials.
Or if the digital book becomes robust and popular enough, the price of one on demand printing could be included in the purchase of the book.
I thought it was cool.