Krishna Bhargav has been using it from IronPython and has written up a blog entry on how to get it working with IronPython 2.6:
As I was looking for embedded database systems, I came across this pure python database called KirbyBase. So I decided that I would make it run on IronPython. So this post describes on how to make KirbyBase run on IronPython and using ipy.exe. Note that I am not looking at integrating this database into C# application yet. [may be in the future post]Using Python libraries from C# is an interesting topic (covered briefly in IronPython in Action of course) which I don't think enough people have experimented with. The need is to create a statically-typed wrapper layer which the C# can use and handles calling into Python and returning values.
In particular I'd like to see a C# wrapper using Ironclad, so that Numpy can be used from C#. There don't seem to be any open source libraries for .NET that are anything like as comprehensive.
There is also Curt Hagenlocher's Coils project which (if completed) could automatically generate the wrapper classes from Python class definitions.