In this photo illustration a sat nav is seen attached to a windscreen of a car in front of a sign telling some motorists to ignore their satellite navigation devices on January 6, 2012 in Symonds Yat, England. Satellite navigation devices (or sat navs) have become increasingly common, however the problem of mis-directed motorists following out-of-date or inappropriate instructions has become so serious it is to be tackled at a government summit in March. (Photo illustration by Matt Cardy/Getty Images)