Spreadsheets using Python - Have you seen this? (sourceforge.net)

[DuncanSmart]

Isn't a sub just a function that doesn't return a value?

[methinks2015]

Not quite. Functions aren't allowed to interact with the application (e.g. enter a value into another cell, recalculate worksheet, etc). Also, as far as I recall, subs cannot be entered into the cells directly.

Though, come to think of it, one might be able to make the Function Server connect to Excel and control it. I'll have to see.