comment_terms
This module allows users to edit a node's terms when adding a comment. Much in the way that Drupal's project module allows you to edit an issue status when posting a follow up. I use comment_terms on this site for the same effect. When commenting on an issue you can change its status, assignee, etc...
Comment_terms started by supporting taxonomy terms. Now it supports categories, workflow states and attachments. But "supports" may be too strong a word. It uses some form APIs in ways... let's just say creatively. Meaning future changes to Drupal may break it, and hopefully those changes will bring better ways to accomplish this sort of thing.
You can find comment_terms in my drupal sandbox.
