Speak Freely is a plugin for the Elgg framework that allows anonymous users to comment on public content. Includes built in recaptcha controlled through the admin settings, ability to customize the display name and icon for anonymous posts.
Working on creating a recaptcha module for Elgg. Currently supporting version 1.5 to 1.6. Elgg version 1.7 will bring token changes that will need to be reworked.
KnowledgeFrame is a proven, mature Java framework for agile design and development of sophisticated business database applications based on live metadata and live business rules, using a declarative approach. Links to RETS 1.7 protocol.