The best thing about my workspace is that I have a big white wall above my desk where I post things that catch my eye.
The desk itself is a hand-me-down from one of my old employers. It's extremely heavy although quite small. The slide-out keyboard tray is a favorite napping place of the Q Collective cat, much to the detriment of my productivity.
My pride and joy is my new iMac... which is almost 2 months old now. I often have iPod and digital camera cables plugged into the back and laying on the desk. My desk always holds coffee or water, a mug of pens and other tools, my calendar, a family photo, post-it notes, to-do lists and mail.
When I am deep into a project, the desk is covered with folders, books, sketches, photos, rulers, food etc. I can be really messy but then get a sudden urge to straighten up my desk.