The Book of General Ignorance
By John Lloyd and John Mitchinson

A humorous but informative book for trivia fans.  This book is about things we all think we know, but we're wrong!
Like what did it mean when a Roman gladiator got a thumbs down?  Or what did aborigines hunt with boomerangs?
If you think you know the answers you are probably wrong.  It has a four-star rating on Amazon.