I've been using the CSS-Friendly Adapter project for a few years. It's a fine solution for getting the mucky overly-tabled asp.net menus into nice unordered lists. Because MultiStore uses the ASP.NET menu control, it's possible to use the adapter. I have it installed, working and styled to my liking.
There's a codeplex project, but you should download it from here (not me, and I don't know the guy):
http://cid-635c8e2bf4822d7c.skydrive...SSAdapters.zip
As a side bar, this Adapter project (I think) really exemplifies the power of the .NET platform and ASP.NET.
Bam. Gorgeous example of the power of c#, extending classes and overriding methods.Code:public class MenuAdapter : System.Web.UI.WebControls.Adapters.MenuAdapter