The baby has decided that she has no interest in staying in her crib any later than about four in the morning. She doesn't exactly want to wake up after that, but she has no intention of just lying peacefully in her crib either. She wants one of us to get up and do something entertaining.
The first phase of this task falls to my wife, who has the baby responsibility until five-thirty. At that point it switches to me, and I take the baby upstairs and get her strapped in to the Miraculous Baby Hypnotizing Machine, also known as her swing. This machine isn't all that miraculous when she's fully awake and feeling cranky, but in her current state of partial awakeness it does the trick. The swing rocks back and forth and she's asleep within seconds, leaving me bleary-eyes but not particularly busy. The perfect condition, in other words, for getting to work, thus allowing me to get done very early as there are no distractions to slow me down when everyone else in the house is still asleep.