This is one of my favorites from 23 Things. The many applications for Wikis are exciting. I really like the fact that it is easy to use. I just started a class read aloud of "Hector Mireles and the Battle of the Alamo" and I think a class Wiki might be a neat addition. I have been using the strategy "Stop-n-jot" - I think this will actually be better. Instead of having students offer to read what they have written, they can actually post them on our Wiki. My students really enjoy using computers - so this will add to their writing pleasure.
I thought the video from CommonCraft was very helpful. I like the way they present their videos to make technology more user friendly.