Report #27 in this series discussed the 'wiki' method of online information-sharing, and its educational uses. A wiki is browser-based collaborative writing environment, in which a community may amass and exchange information on a particular topic, and to which anyone may contribute without having Web programming skills. In the current study, seven wikis are reviewed: "EditMe," "MediaWiki," "seedwiki," "Socialtext," "Swiki.net," and "WikkiTikkiTavi/ InterWiki." The educational potential of each is discussed.