As Easy as Pi

I had a Pale and Geeky Christmas - my cousin gave me a sonic screwdriver, friends gave me a Doctor Who miscellany, and my parents gave me a Doctor Who t-shirt, a puzzle book, and four very geeky books.  One was As Easy as Pi, a volume of number trivia.  It's a perfect commute book, with essays ranging from a paragraph to a few pages on number-related topics.  From explaining where numerical phrases came from (or may have come from) to why buses seem to come in threes, it's diverting and unchallenging.  Just the thing to read during snow-lengthened commutes.