Mucho Menus is an implementation of the "mega menus" web trend that has gained popularity in recent years and months.
Setup demonstration video
Watch this YouTube screencast, "Setting Up Mega Menus in Drupal using Mucho Menu" for a demo of how to set up Mucho Menus on your website:
More about this module...
This module allows users to create mega menus that have mini panels as their flyout content. The benefit is that ANY type of content or UI can be added to the menu flyouts.
The module has panels_mini as a dependency. It could be extended in the future to allow other types of panels, but mini panels were the most logical choice.
Additional extensibility options could be jquery/js triggers and events on show/hide of the menus, so that a video could automatically be started, for example, when a menu flyout appears.
A demo of the module in its current state can be found at http://www.billkrause.com. This website features the first public implementation of this module. Also attached are several screenshots of the module in action, both the end-user experience and the administrative interface.