I'd add Tiki Wiki to the list of there for ones worth considering. It has way way too many features, but is really nice for getting just about anything going. Typo3 is an amazing product, but I personally find Tiki Wiki to be easier for someone who doesn't want to do any programming and knows just enough web to properly install scripts, database, etc. and do some markup. Typo3 is a great solution if you have the time to learn it and maintain it, but I'd personally say that if all you are trying to do is a favor job for someone you can get Tiki Wiki going and working acceptably for plebs and not have any trouble maintaining it and updating it. Drupal, Joomla, and WordPress all feel very inefficient to me for groupware software. They are easier to get going, but I find them annoying to actually use.