London - First constructed in the 1950s as part of an atomic research program, the 2.5-ton WITCH computer became the "world's oldest original working digital computer" after a museum in the UK restored and then rebooted it on Tuesday. Unlike today's nearly mute devices, the massive computer clicks, clacks and flashes like something out of an old sci-fi movie. "In 1951 the Harwell Dekatron (the other, less-amazing name for the WITCH) was one of perhaps a dozen computers in the world, and since then it has led a charmed life surviving intact while its contemporaries were recycled or destroyed," Kevin Murrell, a trustee at the UK's National Museum of Computing, said. The computer outlived its usefulness in atomic research by 1957 and was used as a teaching device until 1973. It went on display briefly before being dismantled, the museum says, and then was "rediscovered" by volunteers at the museum in 2008 or 2009. The computer's "flashing lights and clattering printers and readers provides an awe-inspiring display for visiting school groups and the general public keen to learn about our rich computer heritage," the museum says. It's also a healthy reminder that not all gadgets have to die after a single product cycle. At a time when iPhones are swapped out every 12 months, the TI-83 calculator and this computer are among the only pieces of technological machinery that have survived for decades. The WITCH, however, doesn't serve much of a practical purpose at this point. (FA)