Re-Usable Controls in WPF

MSDN Article - Developing Reusable Controls with the Model-View-ViewModel Pattern
http://blogs.msdn.com/b/nathannesbit/archive/2009/03/13/developing-reusable-controls-with-the-model-view-viewmodel-pattern.aspx

WPF: Binding to Properties in your UserControl or Window
http://decav.com/blogs/andre/archive/2007/05/27/wpf-binding-to-properties-in-your-usercontrol-or-window.aspx