I just read a very interesting article over at PickTheBrain.com on the realities of productivity for "information workers". As a web developer/programmer/whatever-they-call-me-this-week, I fall into this category. One of the main points to the article is that most of us aren't mentally capable of being in super-productive mode for a solid 8 hour day. I agree. I typically get 4-5 hours of good problem-solving work done per day. That is typically in two distinct blocks of time (one early morning, one post lunch). The rest of my "work day" is spent reading/studying or (god forbid) meetings. Sitting and thinking appear as if you're not busy, and therefore, not productive. The article talks about breaking up the day with more re-energizing tasks that most people cannot do in the office. Telecommuting is presented as one solution for this. I certainly do my best work in my studio with the door shut and music blasting ... not in a cubicle, at the top of a stair case where people stop and chat loudly throughout the day.

Anyway ... an interesting read:

Why the 9 to 5 Office Worker Will Become a Thing of the Past