At TechReady, Mitsuru Furuta from Microsoft France built a WPF Visual Linq Editor. The Visual Linq query builder is a Visual Studio 2008 addin. It's a designer that helps you create Linq to Sql queries in your application. Both C# and VB projects are supported. VLinq also acts a great learning tool because you can put together queries in the visual editor and behind the scenes it is generating C# code behind that contains your Linq query.
The VLinq project as any designer helps you to build graphically Linq to Sql queries but we wanted to keep it visually very close from the code. The goal is not to hide the generated code but to make it visible in the designer. It's a kind of mix between a classical designer and a graphical intellisense.