Jim Hungunin posted a paper about an implementation of Python for .Net
IronPython: A fast Python implementation for .NET and Monohttp://www.python.org/pycon/dc2004/papers/9/IronPython_PyCon2004.html
In this paper, he started out trying to show why .Net is bad for dynamic languages. But in the end, he believes .Net is actually good for dynamic languages, at least for Python.
Check it out.