Uncle John's Bathroom Reader is pretty good. It's full of 2-3 page articles. Mostly, kind of a fun facts kind of thing. It also has some longer, more in depth articles that take more than one sitting. A couple of years ago, the book had a real nice history of US and Iranian relations.
Almanacs are always good. Also the Bible's not bad. It's full of short stories, parables, sayings, etc.