As I have stated in some of my older posts, wikis are great tools to use for collaborating, compiling research, and distributing information. There are various free wiki sites that you can use for your personal use or classroom. Here are some further resources with ideas on how to teach and use wikis:
Wiki Walk Through – has a chart which compares the major free wiki sites
The Art and Technique of Wikis
Wiki Wisdom: Lessons for Educators
Some wiki examples:

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