I have always been a night owl. My most productive, most creative time to work is from 7:00PM - 2:00AM. When I worked for an IT shop, I was usually up working late, coming in late (9/10 AM), and going home late. I got so much work accomplished between 4:00PM and 7:00PM.
Friend of mine was a morning person. Came in around 6A and said he loved the couple of hours to work without being interrupted. I loved the couple of hours after five where I could work without being interrupted.