How do you use blogs, wikis, etc., in your postsecondary setting?

We've had at least a few people respond to my last thread who are working in the postsecondary environment and who use blogs, wikis, etc., in their instruction. I thought we could start another thread where those people can give summaries of HOW they use them: what are the GOALS of instruction; what their DESIGN is; what their PURPOSE is; what WORKS and what DOESN'T work, etc.

I love hearing what...
Original article from http://www.classroom20.com/xn/detail/649749:Topic:408824