I like the format of Howard Rheingold's new mini-courses. Topics include:
- Infotention - a mind-machine combination of brain-powered attention skills and computer-powered information filters
- Network Literacy
- Introduction to Cooperation Theory
- ...and more.
Each is a single box on the web page with tabs: videos, more videos, resources, and fresh links.
It uses the Drupal platform with the Social Media Classroom codeset (I'm not sure if this is set up as a Drupal installation profile or if it is a fork of the Drupal code.)
He also offers larger courses via wiki. All free, all aimed at increasing the 21st-century skills of whoever would like to learn them!