AJAX folder tree that can be dragged and dropped

By dragging and dropping the folder icon with the mouse, it is possible to replace it with a favorite place by AJAX. It is quite interesting.
First of all it is a demo screen, like this.

Folder tree with Drag and Drop capabilities Demo

Carefully, you can also move the virtual icon of the folder together. It reproduces the operation feeling of explorer.

The script itself is here.

Folder tree with Drag and Drop capabilities