This is about a smaller image as part or above your wallpaper.
The best way to describe it is a rotating image desklet.
It was put forward here by ADComp: http://crunchbanglinux.org/forums/post/20061/#p20061
I always found it a great little script but it seems to be forgotten and had to be a little bit updated: http://pastebin.com/Ggs57V59
What you need to edit: link to image directory: line 12
Time to change image: line 15: in the script I have opted for 100000 seconds, so for a hardly rotating image (especially when you only have one image in the folder); just to make clear you also can choose for that, a non rotating image for a while.
Save the script as image_desklet and make it executable.
Put it in /home/user/.scripts with a symbolic link to /usr/bin
ln -s /home/paul/.scripts/image_desklet /usr/bin/image_desklet