Resolver One is a Rapid Application Development tool with a spreadsheet interface.

It is written in, and completely scriptable with, IronPython (Python for the Microsoft .NET framework). This project hosts the code and spreadsheets used on the Resolver Hacks website - which shows how to get the best from Resolver One (and have fun).

Resolver One, currently Windows only, is free for non-commercial use. You can download it from Resolver Systems.