Usually the only part of my wallpaper I see is a small bit on the bottom left side that says "time to move on".
Do wallpapers aid your productivity?I don't keep my icons on my desktop and rarely see the full desktop unless I have just reboot.
On my other pc I made it a rule not to allow any wallpapers that weren't created by a member of my family. This encouraged artistic productivity in both my daughter & myself, while we tried to create something we could both live with. (we shared a single user account on it)
We eventually had a collection that was large enough to build a website for them, which was my first real "coding project" (I barely knew any html at the time)
I think more important than the actual wallpaper is your color scheme. It has to be comfortable or you will end up not able to use your pc for any long length of time.
While it was quite beautiful, this green theme was bad for my productivity because it caused me to get a headache after about an hour of pc usage (for my daughter it had the opposite effect and she loved it):
Do wallpapers aid your productivity?In case you are wondering why Windows default themes are based on blue, studies show that blue encourages productivity better than any other color. Windows color defaults were designed with office workers in mind. I can't remember the link to where I found that info, but I did come across it while doing some research on how various colors affect the human mind.
That could be very true, and it used to be my favorite color, but from experiences with Win98se I have hated that color ever since (too many BSOD's).