Although I agree with
Deborah909's sentiments about the poor naming of this
device -
I really want one.
I currently have a real problem with getting up despite having possibly the loudest alarm clock of all time. It looks like one of those normal electronic alarm clocks with a button on top that you push in to turn the alarm off and click out to turn on. It does however conceal a very real bell inside it and rings with such ferocity as to often shake itself off the table. It is so loud that it often succeeds in waking me by waking up my housemate who lives on a different floor to me, so that she comes down and wakes me up herself before beating me to death with a club for waking her up. Either this, or I wake up immediately with a start, turn the thing off, fall back to sleep, and later when I do get up I wonder why my alarm didn't go off.
The Zen Alarm Clock, with it's progressively increasing chiming rate, might well do the trick. For example phone calls usually wake me up eventually due to their persistance. The Zen Alarm clock strikes just once, then waits a bit, strikes again, and so on, the chimes getting more and more frequent until you wake up. This happens over the course of 10 minutes.
The thing I rather balk at is that this device costs 100 dollars - or 60 quid to me. That's rather stupendously expensive for an alarm clock if you ask me.
Not that I want to advertise them, but you can look at: http://www.now-zen.com if you like.