I work 7-hour days, but I might work 2 or 3 hours during that time. A lot of the time I find the work unbearable and can only bring myself to do it in short intervals. When the task is interesting, involves my skills, and I'm making progress, I can work for hours with almost no breaks. It really is an emotional thing. I won't force myself to do anything that is really painful because it ruins my mood for the whole day. At the same time I feel guilty of days I get little or nothing done and I feel trapped by the time constraint of the work day, even though I work from home. I would really like to make a deal where I work independent of a work day, with no set hours and no expectations, and not feel like I'm on call all day, so I can do things other than work through the day and not feel like I'm cheating.