I think the alarm clock is like family: when it does its job, it is irritating but later we're thankful for it.
Even the name brings up stark images of danger and panic. Alarm! You have forgotten to feed the baby. Alarm! You are late for a flight. It is a strong word, and to use it on a mechanical device seems tad melodramatic. I say mechanical because for a very long time that is what alarm clocks were. Wind-up toys that tick-tocked all night and rattled you out of sleep when the time was right. There is many a soul among us who would have loved to bring down a hammer on these miserable machines.
Time passed, somewhat ironically given the device's job, and electronic clocks emerged. These contraptions used annoyance at the core of their wake-up technology, not shock and awe like their mechanical predecessors. They were extremely effective, the same way a mosquito is in a quiet dark room -- small and very difficult to locate. By the time I stumbled around in the dark and managed to pacify them, I was wide awake. Now things have become fancier, and clock radios allow me to wake up to NPR stations anywhere in the country.
Time being what it is, the future for these devices could get philosophically intriguing. Perhaps someday, they will get into our heads. Gone will be the days of physical torment. In its place, I propose a little voice that talks to you every day at 5:00 am:
"Do you know what is happening to your 401k? Ever wondered what will happen to your family if something were to happen to you? You might be right -- your job is getting cut soon. Did you lock the car? Is that a car alarm I hear? Better get up and see to it."