Speedo not working

[sddsddean]

51 reg Mondeo. The wife was driving along this afternoon when the speedo stopped working(needle went back to zero) and the odometer(which is an LCD display) became a line of dashes. First thought was the cable had snapped... until I remembered its all electronic!!. Anyway, went out to the car about an hour after she got home and it all works fine again. So this is either a one off or an intermittent fault. Any one else had this?