Back in the days when I had more than one alarm clock I found it was counter productive.
At one point I had 3, and because I had 3 I ignored the first two. What happens when 1 of the three of them doesn't go off? I sleep in.
These days I have just the one on my phone, and I'm much better off with one alarm.
That depends...some are self funding, some turn a profit.......some are money pits.
i point my laptop at http://www.nakedalarmclock.com/ disable all power saving options and turn the volume up to 11. anything less and i aint in work.