Very clean and minimal desk and desktop, easy(right hand) access to Notebook+Pen, easy(left hand) access to Coffee and Water cups that are placed on top of unused mouse pads. Silent mobile on the monitor stand, unhooked telephone on left hand side.
Reference books on top drawer. At the end of the day cups go to sink, notebook and book go back to their respective places.
Most important for productivity separate machines(laptop for browsing/email/IM, desktop for work) for separate tasks and starting work at a proper(quiet) time.
I have always found that if i can get the above right i have a good day.