For some reason, I can always get more done during the odd hours.
I can write better at 1:30 a.m. than I usually can at 1:30 p.m.
I can knock out website changes or development better at 5:00 a.m. than 5:00 p.m.
I believe what it really boils down to is the lack of distraction.
My wife and I usually get the kids down for bed by 8:00 p.m. After that, there is a sense of calm in the house and it is a great time to get projects done.
After they are all asleep, they stay in bed until about 7:00 a.m. This means that if I wake up around 5:00 a.m., I have a solid 2 hours that I can use to get things done.
I'm currently writing this post at close to 1 a.m. I just got a burst of energy all of a sudden, so I figured it was worth writing a few blog posts as well.
My next step is to really focus during these hours to get books, eBooks, and other projects done and out to the market.