school, works flat-out all day, gets home for dinner and bedtime with the family and then works until midnight. During speeches to college students, he sometimes asks them why they like to sleep late on

weekends. 'Why would you sleep when that's your time to live?' he asks. 'Sleeping isn't living. You sleep when you die.'

In other cases, entire companies assume a no-sleep culture. In James B. Stewart's 2005 book 'DisneyWar,' Disney studio chief Jeffrey Katzenberg was said to sleep only a few hours every night, reporting to

his office by 5 a.m. He sometimes scheduled major meetings for 7 a.m. on Sunday, Mr. Stewart reported. Not surprisingly, Mr. Katzenberg insisted that all the meeting rooms be stocked with Diet Coke.

People now sleep about 20% less than they did a century ago, the nonprofit National Sleep Foundation estimates. But as I have written, most people need seven to nine hours of sleep. Without it, we snack or

drink caffeine or exercise to compensate. And we get sleepy. The foundation's 2008 poll of 1,000 Americans found 36% are drowsy or fall asleep when they are driving; 29% become very sleepy at work, and 20%

have lost interest in sex because they are just too tired. Researchers blamed part of the problem on overlong work hours.

Readers, are you one of these high-energy, no-sleep jugglers? Can some people actually function this way indefinitely, leaving the rest of us lagging behind the evolutionary curve?