While I don't thing menu's are very usable over the web, sometimes you have to have them cause the customer wants them. I just found this on StronglyTyped.com:

ASP.NET Menu: "ASP.NET Menu is an ASP.NET Server Control that allows you to easily add powerful and attractive menus to your web site or web application with just a few lines of code. " I'm using ASP.NET Menu in a project at work. It's pretty well built and has a clean object model. I tried a few others but some of them were quite tedious to use. One for example had 3 or 4 different files that were required (.ASCX, .CSS, .XML, and the .ASPX). With ASP.NETMenu it's just a server control tag and CSS of formatting. Very clean.

Looks pretty good. I'll keep that in my toolbox. Thanks.