When generating database mappings using LINQ to SQL, which tool allows you to create entity classes using a convenient graphical interface?

The Object Relational Designer (O/R Designer) provides a visual design surface for creating LINQ to SQL entity classes and associations (relationships) that are based on objects in a database. In other words, the O/R Designer is used to create an object model in an application that maps to objects in a database. It also generates a strongly-typed DataContext that is used to send and receive data between the entity classes and the database. The O/R Designer also provides functionality to map stored procedures and functions to DataContext methods for returning data and populating entity classes. Finally, the O/R Designer provides the ability to design inheritance relationships between entity classes.