This is the desktop I currently have on my office PC at work:
I think Windows 2K theme is a MUST in term of simplicity, and having to deal with the PC for the most of the time, I have chosen something plain and simple that never hurts.
Also I like to keep my "office" PC desktop in perfect order: clean desktop, the less icons I can, plain and comfortable.
You know, when you work you don't care about having a good-looking desktop, but you prefer a functional one instead.
The desktop of the other PC (the one I use for "testing" purposes) is a real mess, but I need to have everything available when I need it so I fulfilled the desktop with documents, folders and links.
This is the wallpaper though. I don't know who chose it, probably the other guy that works with me, but I find it kinda funny:
