Lee Lefever of Common Craft has done it again by creating a three minute something video on using wikis. It's available in more than one format from more than one video source, and he has included a captioned version and a transcript.
Text Transcript: http://www.commoncraft.com/transcript-wikis-plain-english-video
Captioned Version: http://dotsub.com/films/wikisinplainenglish/
I thought we'd have the captioned version here since I copied the code from his site so people could view it from this blog, but that is not the case.
His best screens are examples of the simplicity needed for the small screens of portable media players.