Yesterday, driving back from Milton Keynes a stone flicked up and hit my windscreen.  Although it sounded more like a brick (slight exaggeration) it has only left a chip in my windscreen.  Time to test the boys (and girls) from Autoglass, claiming to come to a place convenient to you, etc, etc.  Shame we only etch metal, if we could etch glass I maybe able to do something about it.