Hi guys,
Skyline Virtuemart Nested Accordion is a module of Joomla! that displays Virtuemart categories as multilevel accordion menu. The accordion effect is written in native mootools javascript which is supported by Joomla! core so that there will be no javascript conflict when you use this module.
Try this here: http://www.vnskyline.com/demo/index.php/joomla-modules/other-modules/virtuemart-nested-accordion
Thank you.