Or power outage lights, as I just learned they are called, come in handy when it suddenly goes dark because of a power failure. This is not the kind we have, but I didn't want to spend a lot of time searching for the exact one. I also know nothing about the site, it was first in the list of search results.
We have one that my sister in law gave us for Christmas a few years ago. It plugs into an outlet and when the electricity stops flowing to it, the light comes on. This is nice when it happens at night, as happened to us a few weeks ago. We saw the lightning and a big clap of thunder popped then it was dark. Except for this light coming from behind the entertainment center. It just happens to be the only outlet not used regularly. I had only recently plugged it back in (ask me why it wasn't always plugged in-I don't know) and was glad I had. We had a boy here visiting and while he had just fallen asleep, our son had not and the whole event shook him up. Being able to get to that light and then light candles helped keep him calm.
We figured it was an area wide outage until Tony looked towards the neighbor's house and they had light. Turns out the lightning blew a fuse in the power line across the road and about 6 or 8 homes are served by that fuse. It's too bad both of the boys were asleep by the time the power company arrived to solve the problem because it was neat to watch how they changed out the fuse.
A couple of nights ago we took my parents out for burgers and when we arrived home the power was out again. It had been off for nearly half an hour when we got home and was off for nearly two. It was still light out when we returned so we didn't notice right away. The flashlight was still working though. I'm glad we have it and that it got plugged back in!
If you don't have one of these, I recommend them. It's nice to have an instant light source when the power goes off so that you can get to your other sources of light easily.
This post is part of the Preparedness Challenge at Homestead Revival.