The new alarm clock is built in to a mobile phone. The subject sets the desired alarm time as normal and places the phone nearby (usually beneath the pillow). The phone analyses the subject's 'sleep movement sounds'. Twenty minutes before the alarm is set to go off, the phone determines when the subject is making 'almost awake' sounds, and gives off a soft alarm signal.
If I had something to tell me that, despite my desire to get more sleep, it really would be better to just get up early than go back to sleep and force myself to wake up when my alarm goes off, I think I might be more prone to do so. As it is, without such reassurance, I sometimes will wake up like 20-30 minutes before my alarm clock is set to go off but then go back to sleep, only to regret that decision when I try to break out of the deep sleep I'm in when my alarm goes off. I hope software/alarms like HappyWakeUp become ubiquitous.