I just found a great page on the C2 wiki called Mental State Called Flow. It has some good discussions about getting into a state of mind where you can get stuff done. I have found that when I work from 7am-4pm I can get at least four hours of hacking done before 9am. This is because for the first hour it is only me and a few other people spaced out in the office and then from 8-9 everyone is waking up, getting coffee, and checking email so interruptions are close to nil.
Eric Davis