Add a REPL Console to Your .NET Applications
Microsoft is starting to push IronPython and IronRuby as the way for end users to customize their applications. Once such example is Microsoft Dynamics, which is using IronPython to allow state and local governments to create complex fee schedules. These are used when the business rules governing a decision are too complex to be represented by normal lookup tables and change to frequently to justify a traditional development cycle.
Since Microsoft Dynamics is a closed-source application, Microsoft is turning elsewhere for examples of how dynamic languages can allow users to customize their experience. Once such example is Witty, an open source Twitter client.
A novel feature in Witty is that it includes a REPL console. Exposing the console is incredibly simple. Simply instantiate a ConsoleWindow object, pass in the objects you want your end-users to be able to access, and display it.
var console = new ConsoleWindow();
For more on Dynamic Languages on .NET, check out the Pumping Iron video on Channel 9.