I have an affinity for python, but I work in a .NET environment, so I was looking into Iron Python, and wondering what it would be used for.  
Could you write an app in it? or is it for adding a scripting language to your app?
How do you guys use it?
You can use it for cool things like having an embedded web server within your application which can be developed with one of the available Python web frameworks. It is much easier and smoother to develop for than hosting an ASP.NET web server within your application. CherryPy for example comes with a builtin web server as well that should work fine with IronPython with a few small modifications.
Iron Python : what are good uses for Iron Python