Submission by Matthew Smith
Peerthought is a wiki without wikiWords... make sense? It's the most gui-ized wiki you'll find so that bringing non-technical people into it is a snap. Currently in beta release 2.0 adds some exciting features. Free trial is available for sign-up online at http://www.peerthought.com. Yes... it is a commercial product, and once you use it, you'll understand why.