http://flightaware.com/live/flight/UAL1220/history/20061010/1429Z/KSEA/KDEN
This flight between Seattle and Denver is showing that it has arrived, but the graphic shows the flight in Progress (usually–sometimes the graphic jumps back to Idaho), and it is not scheduled to arrive for another hour. looking at the history, they all drop off tracking near this point.
Mine friend in his companies Citation did the same thing…