Video: http://www.youtube.com/watch?v=Oi3QKuFugWk&hd=1
edit - link to project: http://pytools.codeplex.com
My understanding of the difference between the links: Pytools in general lets you run Python programs in Visual Studio. Pyvot is a part of Pytools that lets any Python code on Windows (including code run in Visual Studio) connect to Excel.
Video: http://www.youtube.com/watch?v=Oi3QKuFugWk&hd=1
edit - link to project: http://pytools.codeplex.com