Never quite get round to finishing that book you've been meaning to? Still putting off cracking open the Dickens biography you got for Christmas? Recalcitrant readers take note: a publisher in Buenos Aires has created a book written in disappearing ink.El Libro que No Puede Esperar (The Book That Can't Wait) comes in a sealed package and as soon as you start to turn its pages, the ink begins to age... and fade. Readers have less than two months to tackle the tome before the text toddles off into the ether.While it might sound as though it was created by a sadistic speed-reader who wanted to torment rather slower bookworms, it's actually a bid to boost excitement about real, rather than digital, books. It'll be be a real cliffhanger if you don't finish it in time.