Asleep on the Job

I have this thing where if I stay up to a certain point in the middle of the night, I won't be able to sleep until mid-morning, which wasn't really a problem until I got a real job. And even then, I was able to keep it somewhat in control. I mean, I made it through the day like an automaton, but still, I made it through the day. Except for this once, after a few days in a row of getting hardly any sleep, I just passed out at my desk. I was only going to close my eyes, and the next thing I know my co-worker is poking me awake. At least my boss didn't find out!