This plugin is no longer maintained.
Turing Test is an antispam tool that lets you ask your visitors a question before they can submit a comment. "What color is red" or "Type 'foo' in the box" (which isn't a question but you get the idea). A wrong or missing answer means the visitor has to try again. Protects comments, message forms, and registration. (This is an upgrade of an existing plugin for v220)