Terri Van Keuren (from left), Rick Shoup and Pamela Farrell, children of Col. Harry Shoup, commander of the Continental Air Defense Command, visited StoryCorps in Castle Rock, Colo., to talk about how their dad helped to create the U.S. military's Santa Tracker. StoryCorps hide caption

itoggle caption StoryCorps

Geoffrey Nunberg says technology makes it seem as if we're always being watched, which is creepy. Ralf Hirschberger/AFP/Getty Images hide caption

itoggle caption Ralf Hirschberger/AFP/Getty Images