Overview: The following code demonstrates how to create a custom menu control in SharePoint that goes 3 levels deep with the same look and feel as the SharePoint horizontal naviagation.
Prerequisites: A custom list to maintain the data for the menu items must be created with the following columns
Title – Single line of text
Link URL – Single line of text
Link ID – Single line of text
Parent ID – Single line of text
Link Order – Number
Display – Choice {Yes, No]
Item Level – Choice
Level 1, Level 2, Level 3