I've been using Kaloer clock (found in the market) for about 2 weeks now, and I really like it. It has options to force a max volume that's set by you, as well as automatically starting up when the phone is plugged in. I've yet to have any problems with it, and it actually has a nice big display that makes the phone look like an alarm clock when it's running.
Kaloer Clock Android App Review by AndroidTapp.com | Android Tapp. Android App Reviews
^That review seems to be a bit outdated, since I have several skin options for mine, and setting an alarm to go off every day isn't something I have to do every day. Besides that, it will at least give you an idea of what it is and/or what it looks like.