Learned Today: Rails is a Harvested Framework
From ASP.NET MVC in Action (chapter 11):Unlike many other MVC frameworks, Ruby on Rails is a harvested framework, one that was extracted from a real-world application: 37signals’ application Basecamp. Because Ruby on Rails is a harvested framework, all its features have been used in a production environment ...

Never heard the term "Harvested Framework". I think that is a good terminology to contrast the every so often encountered "ivory tower framework".