Well I have an iPod, and a brainwave generator program thingy. I've only used it once, for a sleep inducing preset thing (I've only had the program for like a day) and I put the thing in my ears, closed my eyes and listened to the sounds.

I was thinking to myself I wonder if this thing is going to wo-.... and the next thing I was waking up to my alarm. Only thing is I couldn't remember any dreams

And I did see a preset for ur brain entering the deep sleep phase but keeping you awake, although I haven't used them.

So I'm sure there is a way it can be used, if it works for me (I'll give it a shot tonight) I'll tell you!