I have a database of software tools and I want to be able to have users rate and comment on the tools, and view the ratings and comments that other users have left. To lower the risk of spammers attacking the site, I would like to be able to restrict comment/rating permissions to those who are logged in. At present, the tools are in a list on a static html page as part of a website that is very "non-interactive"; other than the contact form, there is nowhere that users contribute content to the site. We maintain a wiki (of the standard mediawiki flavour) that users can contribute to, and we also have a Drupal installation as a news site. Does anyone have any experience of creating such a rating/commenting system, and whether it would be better to use Mediawiki or Drupal (or another free CMS?), or to try to create something myself? Any advice would be appreciated. Thanks!