You can create standard floatable web tree menu. In this tree menu sample you can see how to use lines. You can also add any html code within tree menu items.
You can create a floatable tree menu. When the page is scrolled the menu stays visible. In this sample only one item and one sub menu can be expanded at the same time.
With DHTML Tree you will be able to create 3-state icons for each item in normal, mouseover and expanded states.
You can create both standard or XP-like types of Tree Menu Dhtml.
This sample uses animation and effects when sub menus collapse/expand.
DHTML Tree highlights the pressed item when the page is opened.
DHTML Tree can save items state automatically!
There is no need to write additional code on a server side to remember what items were expanded/collapsed.