"I once met a guy who works in the production shop at the Exploratorium, the hands-on science museum in San Francisco. He described to me a party the production shop once held, the theme of which was 'Exhibits That Will Never See the Light of Day'. Each worker built one. Among the entries: An ink fountain for the kids to splash in; a booth titled "How Far Can You Fall?"; and -- my favorite -- an exhibit titled 'Is It On?', consisting of a table saw and a strobe light."