I was rewiting the code for WP-dTree to allow for more functions and an admin menu. During this process I decided to add in scriptaculous effects for tree animation. As I had install troubles with other plugins that used scriptaculous, I decided that I would create a plugin that installed scriptaculous for me (WP-Scriptaculous...duh???)and also pointed all other plugins that use it to the right place.
There are options set so that other coders can check for the availability and version of scriptaculous installed and generate errors or fail the install is needed. Hopefully it will make life easier for both coders and users.
As for WP-dTree, a catergory tree has been added with the ability to show child posts. CSS, tree options and effects can all be changed though the admin panel.
Go here to take a look at either one: