Secret No 1: I'm an early riser. Most of my papers are written in the very early morning.
Secret No 2: When you've been at the desk since 5:30 a.m., the afternoon slump can hit you really hard.
So, what does the wise postdoc do, when he/she looks like a living-dead-impersonater at 3 o'clock but has an important meeting at 4 o'clock? Caffeine? Works for the first few weeks of the semester. Running up and down a couple of flights of stairs? Yes, can work - as long as you can still run, and not just shamble up the stairs and moan like the zombie you feel you are. But once caffeine and
Now, let's hope nobody from my department will read this, because otherwise, they'll be banging at my door asking to borrow my wonderful collection of midnight grey sleeping aids, namely the Ostrich pillow light (very helpful), and the Ostrich pillow mini (soooo comfortable, but not really helpful when the sun is blazing into your office).
Just to be 100% precise: No, I don't normally sleep in my office - but I try. Closing your eyes for a quarter of an hour and pretending to sleep is better for you than drinking that second liter of coffee. Or than snacking on non-organic grey tissue.