Anecdata: Years ago, when I was still in the school I had a cheap Chiniese alarm clock with a lever-thingy to disable the alarm. It was quite simple, when the

Anecdata: Years ago, when I was still in the school I had a cheap Chiniese alarm clock with a lever-thingy to disable the alarm. It was quite simple, when the hour hand reached the position of the alarm hand it popped the lever to the raised state, which engaded that dreadful beebeebeep alarm sound. To turn off you just pressed the lever back in. One morning I woke up totally oblivious to why did I wake up - it was cold and still dark out there. In a second I heard a click of that lever (meaning it would start beeping now) and I managed to threw myself to the clock (which I positioned ~two meters from the bed specifically so I would need to stand and go to it => I would properly wake up), disable the alarm and dug back under the blanket with a blissfull feeling in my mind. Alarm didn't sound and I hadn't a single step on the floor with my legs. I was late that day.