"The bulb in the hall exploded!" were the words I awoke to this morning.
"Exploded? So there's glass everywhere?"
"Well it hit me on the head. Where's the fusebox?"
So I found some shoes and my glasses, and we got a torch and checked it out. The fuse had blown, but no sign of the bulb, and no broken glass.
Miraculously the bulb had blown, come apart, and the glass part had luckily bounced off John's head, and landed intact inside a trainer!
Weird. I won't buy those bulbs again.