I like to keep my windows clean so....
I have a place in a nice warm area, so I can have screen savers from any place in the world, and that's the way it should be.
If you go to images.google.com you can search for wallpaper the exact size of your monitor. If you right click your desktop you can set the screen saver to display all the pictures in a directory for a set time each.
A well mowed lawn that the kids did....but,thats just wishful thinking