The S5 Accordion menu is demo'd on the right of this page. This version was built specifically for this template and cannot be transferred to another template. We do have another version that can be used on any Joomla template.
This module is based off the Joomla main menu system module so you can still specify which Joomla menu you want to use with the S5 Accordion menu. The menu is powered off of the Mootools Javascript library but detects to see if the library is already initialized, if so then it doesn't load its own library to stop any conflicts from arising.