Today you see a lot of XAML-like implementations for .NET framework 1.1. XAML (pronounced "Zamel") is part of AVALON in Longhorn and it allows you to describe the layout of applications. Basically, you describe via XAML-tags your controls, events, etc. it's very intuitive.
One of the projects is wfml. You can find the article with the source code here.
Another project which is still in beta is xamlon. Closer to the release date Xamlon will be licensed per developer.
An implementation under the BSD License is MyXaml and it is increasingly successful. I think I will first play around with this implementation 
. An article from the author of MyXaml can be found on CodeProject
I think the developers who first implemented the concept were ic#code. They setup a library XmlForms which can be downloaded here and is used in SharpDevelop.