I use my own photos because it helps to keep me inspired. Looking at 1 image that often I find all the things I did wrong and think about how i can do better next time.
I hardly ever see my desktop. I turn the computer on and my email client and browser open in overlapping, side-by-side fashion automatically. Even when I close one of them, another program is opened full-screen (LR, PS and more). The computer is on all day - I don't watch TV anymore, I watch programing online. So, the only time I actually see my desktop is when I close all programs and turn the computer off before bed.
Sometimes I have company though, so while I'm chatting with them, I show only the desktop. My friends like my pictures and I like showing them. My desktop rotates to a new picture every 30 minutes. Some are even responsible for conversation.