Groovy Menu is a Free responsive Mega Menu plugin that will allow you easily to add an awesome menu on your site and improve website navigation.
The Responsive Select Menu plugin automatically turns any WordPress 3 Menu into a select box / dropdown on mobile devices.
Allows different content to be displayed based on the value of an author-defined drop-down box.
The Responsive Mobile Select Menu plugin automatically turns any WordPress Menu into a select box / dropdown on mobile devices.
Accordion Categories is a Wordpress widget that allows you to display categories in the hierachical order
Category Ajax Chain Selects