What can you do with a 9 volt battery? Not much, it seems.
Whenever we switch between daylight savings and standard time, we get reminders to change the batteries in our smoke and carbon monoxide detectors. My carbon monoxide detectors take AA batteries, but the smoke detectors take the square edged 9V batteries.
It's a pain disposing of batteries because they are household hazardous waste and need to be taken to a household hazardous waste depot. So I have a big container of batteries just waiting for me to take them to a depot. (I will get around to . . . [more]