Cascade
Cascade allows you to easily maintain a web-based Yahoo-like directory of resources using web-based forms. Features include: Uses a SQL database on backend, Manage an arbitrarily large hierarchy of resources, Writes out static HTML pages for maximum performance, Auto-generated "What's New" page, Manages the count of all the items in a particular category and below, Items in the directory can be people and organizations-- not just links, Supports Related Categories, Supports Virtual Subcategories (what you see in yahoo with an @ next to them), Designed to integrate with static content on your website, Auto-generates a footer, Supports basic ratings of content, and Easy to use interface. The public can suggest additions and updates which admins can easily edit and appove. Also includes a basic rating/comment system for all resources.