What would happen if GPS - the Global Positioning System - stopped working?
For a start, we would all have to engage our brains and pay attention to the world around us when getting from A to B. Perhaps this would be no bad thing: we'd be less likely to drive into rivers or over cliffs through misplaced trust in our navigation devices.
Pick your own favourite story about the kind of idiocy only GPS can enable. Mine is the Swedish couple who misspelled the Italian island of Capri and turned up hundreds of miles away in Carpi, asking where the sea was.