I\'m working on a site which needs to be able to support two or more looks, changable at runtime. I\'d hoped to be able to handle the change with a CSS switch, but it looks like
I've done this once before, I did exactly what you described (Made all pages inherit from a custom page with an OnPreInit event). Also I had a custom Application_PreRequestHandlerExecute in my Global.asax.cs for setting Page.StyleSheetTheme for doing image/css changes that didn't require a different Master Page.