I use my iPhone as my alarm clock both at home and on the road. I've been using Ambiance as a sound machine and travelling alarm clock. What I don't like about it is the fact that I can't tell the sound machine to play until it goes into alarm mode. I can tell it to play for five hours, eight hours, etc., but my bed time isn't that consistent. If I have it set for six hours of sound machine and I'm going to bed four hours before wakeup time, it will ring 28 hours in the future.

What are other people using?