eStream PanelBar.NET Pro 

eStream PanelBar.NET allows developers to create powerful and attractive menus for their web sites or web applications in just a few lines of code. The product offers out of the box support for XP styled and Outlook styled navigations.
asp.net menu components c# vb.net webmenu dhtml navigation

.NET SlidingMenu 

SlidingMenu creates z-piled stacks of layers in a browser and client dynamically navigate through these layers. Using HTML inline tags it is not only easy supporting a creative focus, it is fun and it opts for a more efficient use of web space.
menu menus menues webmenu webcontrol webcontrols server control web webpage browser internet slide sliding