This is a really interesting idea. If you think about it, every spreadsheet is a computer program. Excel is probably the most widely used development environment in the world. And it sucks. Big time. Watching the screencast, it looks like this is a great halfway house between bad, ad hoc, spreadsheet development, and a traditional IDE. The choice of Python as the language is a great idea - it's much, much easier for someone than VBA, and it's much more semantically powerful. I'd be interested in discovering whether it works existing Python and .NET libraries.