Having a clean workspace is important. Organization is key to knowing what you have available, what you finished, and what you have left to accomplish. Also, who wants to work in a pigpen?
I am spending part of today cleaning my apartment so I can see what I have left to do. Cleaning thoroughly once in a while in addition to balancing my checkbook and performing other chores helps me clear my mind and ready myself to perform other tasks, like writing papers and practicing.