The number of years a lightbulb has been illuminating a firehouse in Livermore, Calif. The Centennial Bulb, which earned that nickname in 2001 when it marked its 100th consecutive year of illumination, has been in operation for more than 1 million hours and has been recognized by the Guinness Book of World Records as the world's longest-burning lightbulb. At a time when electricity was still a novelty, the owner of Livermore's local utility presented the bulb, then valued at 40 cents, to the volunteer fire department.
