Not a morning person? A new alarm watch--part science, part this-oughta-work--may help. The Sleeptracker monitors a sleeper's movement and uses the information to deduce the stage in his or her sleep cycle. Its inventor, Lee Loree--a former stock analyst who came up with the idea by watching his wife sleep--designed the alarm to go off just before or after the dream stage, REM sleep. You set a 30-minute range on the watch. If at some point in that 30 minutes you aren't in REM, the alarm rings. If you're in REM the entire half-hour, well, it's time to get up.

Loree's idea makes some medical sense. Most people don't move at all during REM, so motionlessness is a pretty good indicator. And it's true that an interruption can cause a sleeper to wake up "confused and miserable," says Dr. Frisca Yan-Go, director of UCLA's Sleep Disorders Center. On the other hand, Yan-Go says monitoring brain waves is the only way to accurately measure sleep cycles.

The Sleeptracker did a decent job of gauging ours. Half the mornings we used it, its soft beeping roused us a few minutes before we normally wake up, leaving us surprisingly alert. For the rest, it sensed no movement and beeped at the end of the time window, like a standard alarm. $149; www.sleeptracker.com