From their page: Knowledge should be free, open, and shared. Connexions is a rapidly growing collection of free scholarly materials and a powerful set of free software tools to help: (1) authors publish and collaborate, (2) instructors rapidly build and share custom courses, (3) learners explore the links among concepts, courses, and disciplines.

I saw this a while ago when I was looking at plone stuff, but then also got from Nigel Boston the following:

Speaker: Rich Baraniuk (Rice University)

Title: The Connexions Project

12-1pm, Monday - 3609 Engineering Hall

Abstract - Connexions is a collaborative, community-driven approach to authoring, teaching, and learning that aims to capture and convey the dynamic, continuum of knowledge by fully exploiting information technology. Available free of charge to anyone under open-content and open-source licenses, Connexions offers high-quality, custom-tailored electronic course material, is adaptable to a wide range of learning styles, and provides tools that encourage students to explore the links among concepts, courses, and disciplines. In contrast to the traditional process of textbook writing and publishing, Connexions fosters world-wide, cross-institution communities of authors, instructors, and students, who collaboratively and dynamically fashion modules, courses, and curricula. This talk will overview the vision, goals, and progress of the project over the past five years. More information on Connexions can be found at http://cnx.rice.edu/