The late Reb Schneerson, the Lubavitcher rabbi who lived in Brooklyn, also saw people all night. He slept for a few minutes in between.

These people are not superhuman. They're just people. But somehow they find that place where they can give all their time. And when that happens, you find that you have all the time you need. It seems that the more time we give, the more time there is.

Bernard Glassman, Rick Fields in Instructions to the Cook