[supergreg]

I remember one IronPython book that made a spreadsheet application that allowed the user to use python itself for the spreadsheet functions. I think it was a great idea.

The software itself was available for download for a time.

[sundaysailor]

There was a startup called Resolver Sytems pursuing this. They meanwhile abandoned it in favor of a different project but did open-source it: https://github.com/pythonanywhere/dirigible-spreadsheet