I found Infinite Jest extraordinarily compelling, hilarious, and endlessly entertaining. I wouldn't go as far to say that it was "hard to put down". The book will fatigue you at points, as there is such a density of ideas within a single page that you need to just step back for the day and take it all in. But I was inevitably drawn back every time to sit down and open Infinite Jest again and again. Maybe it was the prose, or the endearing and terrible characters that DFW make all come to life, or the sprawling mystery plot. I love the way DFW makes these small, minute observations of life that always seem to make me go "yeaaaah I can relate too!" So many unforgettable moments in that book, including the section about marijuana, and the chapter of the kids playing tennis analogized with war.