Book excerpt: With Build Your Own Chain Reaction Machines, you’ll create 13 zany and awesome mechanical contraptions using stuff from around the house. Build Your Own Chain Reaction Machines invites you into the wonderful world of crazy contraptions inspired by the amazing artwork of renowned cartoonist, engineer, and inventor Rube Goldberg, whose wacky, imaginary machines accomplished a simple task by taking a hilariously complicated route. In this entertaining and instructive book, mechanical engineer and educator Paul Long gives step-by-step instructions for making low-tech devices using everyday objects in inspired and ingenious ways. Each of the 13 projects demonstrates how to build the machine's various elements and explains how they work together to make a mind-boggling mechanism that delivers hours of fun and fascination. Machines for Your Room. Be the master of your domain with the Door Knocker, Light Switcher, and Door Opener. Machines for Around the House. Get your chores done (and improve your personal hygiene) with the Plant Waterer, Toothpaste Squeezer, and Soap Dispenser. Machines for Fun and Nonsense.The Flag Raiser, Marble Launcher, Music Maker, and Balloon Popper are guaranteed to both amaze and amuse. Machines for Food. With the Vending Machine, Candy Dispenser, and Cookie Dunker, snacking has never been so fun! You'll also find interesting sidebars on the science behind each gadget, plus tips and tricks for success. Build Your Own Chain Reaction Machines gives you the know-how to create your own incredible chain reactions!