Before you go on a cosmic road trip, feed the residents of New York City to a T. rex, or fill every church with bananas, be sure to consult this practical guide for impractical ideas. Unfazed by absurdity, Munroe consults the latest research on everything from swing-set physics to airliner catapult–design to answer his readers’ questions, clearly and concisely, with illuminating and occasionally terrifying illustrations.