Great tools. Be it editors, debuggers, compilers, OS, VCS whatever we are most comfortable and productive with.
Open standards. This gives us flexibility to use tools of our choice to work with. So no MS Exchange emails solution, no doc, docx, xls, ...
Simple processes. The mundane should be either taken care, or the process should be simple enough so as not to come in between what we love the most.
Extra chair, available nearby. Very useful if we want to discuss something with your peer or during code reviews.
Biggest baddest monitor you can get. Get as much screen real estate as possible. Whatever helps us see more code at once. This includes dual/multiple monitors, though I personally find it difficult to use multiple monitors. So I prefer one single large high resolution monitor.
Comfortable keyboard and mouse placed at proper height and distance.
White board, notepad (preferably unruled), pencil (a pen will not do, most admins fail to see the difference), board markers (multiple colors) ...
The usual stuff that applies to any other desk job - proper lighting, air circulation, space, regular supply of fresh coffee, quiet environment, ...