ArchiCop

Visit ArchiCop @ Codeplex

Make your .NET Code Clean with ArchiCop!
ArchiCop is a Visual Studio tool to manage complex .NET code and achieve high Code Quality. It's very simple to use. 
With ArchiCop you can validate references, project properties and group your projects in layers.
The project is developed using a continuous integration process, with frequent builds and releases in this community of code and documentation. 
If you find bugs or want additional capabilities addressed by the team, use the Issue Tracker to create a new Work Item.

With ArchiCop you get warnings and errors in Visual Studio when developers violate the rules that have being defined.