We have been looking for a way of getting drop-down menus on the top Navigation bar in WSS for a while now. We figured we would need to create our own custom menu control etc, then one of my colleagues installed this Web Part:
This Web Part, created by Yvonne Harryman allows you with a few modifications to replace the standard navigation bar on the top of each WSS/SharePoint page, this new navigation bar gets its data from a WSS list. The list contains the link titles, parent links, display order and more. It even can go as far as only showing links for certain audiences.
I am very impressed by the Web Part so thought it deserved a link back, let me know what you think!