Organising wallpapers in subfolders

What is the simplest a way to have the desktop wallpaper cycle through images that are in subfolders? This is not possible using the normal way of setting a wallpaper in

System Preferences --> Desktop & Screen Saver

The format of the images:

>Wallpapers
-> Folder one
--> one 1.jpg
--> one 2.jpg

-> Folder two
--> two 1.jpg
--> two 2.jpg

It looks like selecting multiple different folders for images for your Desktop or Screen Saver is not a native function. In other words, if you have a hierarchy of a main folder, Pictures, then underneath you have folders (for example) Family, Vacation, and Wedding, and you only want to display Family, and Vacation, there would be no way to do that. I think the simplest would be to create a folder with all the images you want on your Desktop/Screensaver.

I found a way!

You can use the terminal ln -s command to create soft links from all of the folders you want into a single folder.

For example, if these 3 directories have wallpapers located in ~/images1, ~/images2, ~/images3, and you want to use all of them as your wallpapers:

1. Create a wallpaper directory somewhere: mkdir ~/wallpapers
2. Create soft links of all the images from the 3 directories to the ~/wallpapers directory: ln -s ~/images1/*.jpg ~/wallpapers/, for one.

This isn't a real copy, since you're creating soft and not hard links. It'll barely take any space on your hard-drive.

There's a small catch, though: If you add new wallpapers to the directories, you need to link them manually. However, I believe this can be automated using AppleScript or Automator.