The Jawbone up is the BOMB of all bombs for taking naps. Put it in nap mode and it waits for you to fall asleep before setting the alarm. So you can get a prop

The Jawbone up is the BOMB of all bombs for taking naps. Put it in nap mode and it waits for you to fall asleep before setting the alarm. So you can get a proper nap without wondering whether you're taking too long to fall asleep, etc. It can also attempt to time your nap based on your latest sleep patterns. No idea how effective this is. I love this thing just for it's nap mode.