I first heard of Mental Floss about ten years ago, through SSJCPL's subscription to Mental Floss magazine. This is a great publication to pick up, read a short while, and put down easily, if interrupted. It's stuffed with interesting facts, and answers to questions you may never have had an inkling to ask--but wish you had.
Mental Floss also has a wonderful, entertaining website (a banner at the top of the web page features an amazing fact generator! It told me the name of the smallest U.S. president, and included his height and weight.) This website has other snazzy features, including a Knowledge Feed, which is jam-packed with interesting articles and videos--would you like to see Neil Gaiman read "Green Eggs and Ham?" There are also Big Questions, in which Mental Floss reader's questions are answered; Lists (my favorites are the word lists, like the 11 Obscure Regional Phrases to Describe the Cold;) and Quizzes, asking the reader to choose answers to topics such as Jelly Belly Flavor, or Yankee Candle Scent?
Mental Floss: because sometimes you just need to give the noggin a good cleaning.
Courtesy of Cayusa's photostream on Flickr.com. Some rights reserved.
For a quick overview of history (with a healthy helping of irony and sarcasm,) try the Mental Floss History of the World: An Irreverent Romp Through Civilization's Best Bits. This focuses on the topic of world history, in a very condensed form. Readers of the magazine and website will appreciate the side notes, with topics such as "The Quotable Julius Caesar," and "D'Arc Triumphs," and "Name That War!"
You're probably wondering about the smallest president of the United States. That would be James Madison, who measured 5'4", and weighed only 100 pounds. You're welcome.