For over 50 years, The North American Aerospace Defense Command (NORAD) has been protecting North American airspace from aerial attacks. The same technology that is used to protect us is also used to track the annual Christmas flight of Santa Claus and his reindeer. According to NORAD, a network of 47 radars tell them when Santa's sleigh leaves the North Pole and infrared satellites track his flight. Once the sleigh lands there are "Santa Cams" that can track his deliveries. For more information go to noradsanta.org which has videos from last years tracking of Santa, interactive games and activities, information about Santa Claus, information about NORAD, and a link to track Santa in 3D using google earth. There are also daily updates from Santa's staff. Today update: "NORTH Pole staff have advised NORAD that it is the final day to send Santa an email because Santa and the elves will begin loading the sleigh later today. This is such a huge task that they will not have time to check emails!"
This is a pretty fun website!