The old-time, putzing-around inventor may have lost glamour to the laboratory scientist, but Weiss' latest freely structured how-to book is attractive enough to spark a revival. Weiss talks about both practical inventors (those who create devices to solve particular problems) and those who do it just for fun. He classes himself in the latter group, and shows some of his ingenious if perfectly worthless inventions, which include a steam-powered beckoning hand. Also pictured are inventions of da Vinci, sculptures by Tinguely that fit Weiss' concept of useless inventions, a lot of crackpot devices (some of which were taken seriously by their inventors), and a more predictable sampling from Edison, Watt, and their ilk. Mechanical and electrical aids are surveyed, and useful sources of information and materials appended. Sharp, bright, and nifty as usual, the book itself is a beckoning finger with lots of potential application, both practical and just-for-fun.