This really isn't that difficult to do. Working on it right now. Grab RazorEngine from CodePlex. It lets you compile Razor cshtml/vbhtml files into a class at runtime.
You can then take that class, and use it from a ASP.Net server control, inside its Render method. This is a great way to get HTML out of the body of a server control. Much, much cleaner.
Now, you can also add some methods that you can invoke from Razor. For instance, add something like RenderChild. Additionally, you could set the Server Control itself as the Model available to Razor. You could then invoke into the server control. Including doing something like grabbing one of it's child controls and invoking Render.