... The only advantage I can see to it is that most US-based computer apps run really fast at 3am...

I consider that to be one of the biggest pluses to being one of the few up at that hour.

Actually, I was wondering about both of you and your hours tonight. It's not at all unusual for me to be up all night or even all night and day for even several in a row. I try to not do that, but when I know I simply will not sleep, I don't fight it and try to use the time for something productive. My record is 6 days and nights in a row once. Three is not at all uncommon. And two is very frequent.
A lot of my problem, if I actually considered it that, is that I simply lose track of time. The day I quit that 22-year job, I threw all the watches in a drawer and stopped all the windup pendulum clocks and threw away the calendars. I sometimes have to think really hard about what day it is because I rarely reference a calendar or clock and don't watch any regular programming or anything that provides a clue.
Sometimes I have no idea if it's night or day and have to go look outside. Twilight can be so confusing. Sometimes I fool myself when it's twilight and cloudy. It gets light when I think it's getting dark, or the other way around.

Back when I did work outside of home, insomnia truly *was* a significant problem, though, so I do know how it can be for those who have to keep a regular schedule. My worst days were going in and just trying to hang on all day till time to go home.
All through college, I worked midnight to 8 a.m. weeknights, then switched to being awake every weekend. Four years of that left me in a Twilight Zone.