Refinery is a Ruby on Rails content management system for small business sites where the client needs to be able to update their Web site themselves without being bombarded with anything too complicated. It is truly aimed at the end user, making it easy for them to pick up and make changes themselves.
libsas is a Python library to take the pain out of using SaaS APIs. It provides an abstraction layer on top of various APIs, taking care of constructing the URLs, serializing parameters, and authentication. You just call Python methods and receive Python objects. It's like an ORM for SaaS.
OpenLaunch is a Web-based content management system that integrates a broad array of services into a single, fully-featured, elegantly designed Web site. The project aims to eliminte the difficulty of integrating multiple systems into a single Web site by implementing a blog, forum, Web pages, wiki, and (coming soon) E-Commerce and support tickets. It is built around the Torpedo Framework, an open MVC framework which includes support for controllers, forms, and a large number of other very useful utilities.