Alarm clocks, for many people, are as integral to their lives as their mobile phones and computers. After all, if you’re late to work everyday, what’s the good of all the other fancy gadgets you have?

Most of us are accustomed to using our iPods in our waking hours—for the morning commute, afternoon workout, and ride home from work. But you needn’t restrict your iPod’s duties to the daylight. Your ...