I was working on our web site this weekend with Dax.  The requirement  to swap the ‘banner image’ depending on which of our three products was selected.  Didn’t sound to rough, but you always end up down a rat hole!.  Actually, I’m still not sure I understood Dax’s suggestion, but knowing him it’s a clever HTML/CSS hack that I can’t begin to understand. 

Being a programmer, I ended up making a property on the master page class named BannerImageUrl.  This property set the ImageUrl of the <asp:Image /> of my banner image in the master page.  Then, in the content page’s Page_Load function, I cast the Page.Master property to my custom class, and then call the BannerImageUrl function…easy as cake….Now, I just have to get multiple banner images….