My desktop screen saver images at work are all of luscious beach landscapes and turtles swimming in the ocean. To me this is the essence of peace and calm. I catch a glimpse of these images on the my second screen as they alternate and immediately feel the serenity.
Just a few milliseconds can change your entire mood and outlook. Take advantage of that every chance you get and it will make a huge difference not only in your work day but in your overall mental well-being.