I have not used an alarm clock in 20 years, I have dogs and a cat.
Seriously, 20 minutes in the snooze mode makes the rest of the day just fine, tough to do it at work, though!
In NYC, they have places to take naps for 20min - 1hour. They provide a bed, ambient music, etc. More of a recliner than a bed. I used to skip out for thiry minutes at about 2pm.
Of course, I was a Managing Director, so no one knew or asked where I was.