Imagine waking up with a bomb beside your bed. You have 10-seconds to cut one of four wires if you want to stop the countdown timer. This sounds like a nightmare, but it's not. It's just the defusable clock.
Oh my, teachers in a rural Ugandan school were unknowingly using a live bomb as a bell. They would bang the bomb with stones to call the school's 700 students to class. It was a miracle nobody caused it to detonate.