Two recent (pre Christmas) acquisitions that I have read present a nice complement to each other.
The first is The Second Book of General Ignorance, put out by the team behind QI. A celebration of curiosity it looks into questions that people think have blindly obvious answers (such as How many legionaries did a Centurion command? A: 80 or so). Thanks to this book I have a new found respect for French military accomplishments, can no longer say it's cold enough to freeze the balls off a brass monkey, can't make short jokes about Napoleon, and still can't understand how the British live in such small spaces. The only downside to having read the book is that some of the information in it comes from the current season H of QI, and it means I know straight away some of the answers. Such is the burden of knowing things.
The second book is The Areas of my Expertise by John Hodgman, better known as the PC from the Mac vs PC ads and for his appearances on The Daily Show. The Areas of my Expertise also presents itself as a source of useful information, but rather than the question and answer format used in The Second Book of General Ignorance, it follows a more traditional almanack style, mixing list, tables and anecdotes to provide information on matters including the Hobo War, Werewolf transformation tables including the effectiveness of various traditional defense during the month, US presidents who had hooks instead of hands, advise for aspiring writers, combat techniques and more. It is also almost entirely fictional (John Hodgman is a real person who was formerly a literary agent, so that bit is true). On a practical note, the list of 700 Hobo names should make a great source of passwords that are unusual but easy to remember.
So there you go. One book that titles itself ignorant and provides truth, and the other that proclaims truth and provides fiction, but both well worth reading.