FeatureToggle is now available via NuGet
Just search in NuGet Package Manager for FeatureToggle or in Package Manager Console:
PM> Install-Package FeatureToggle
PM> Install-Package FeatureToggle.WPFExtensions
The NuGet packages are the easiest way to get started, they will create an example feature toggle and app/web.config entries to help you get started.
Project home page: https://github.com/jason-roberts/FeatureToggle/wiki