Plugins - BrainBuster
Add to favoritesBrainBuster is a logic captcha — a test to try and tell computers and humans apart via a simple logic puzzle, math problem, or word problem.
The big benefit over typical image based captchas is that a logic captcha is fully accessible for visually-impaired users who use screen readers.
http://code.google.com/p/robsanheim/wiki/BrainBuster
http://robsanheim.googlecode.com/svn/trunk/brain_buster
Rails' (MIT)
Security
Note: Current version is broken but follow steps at http://groups.google.com/group/brainbuster-discuss/browse_thread/thread/47db84a001edb856 to fix. Hopefully, the author will fix the current version but it's already been a couple months.
I found the corrent URIs:
Hompage: http://code.google.com/p/robsanheim/wiki/BrainBuster
Repository: http://robsanheim.googlecode.com/svn/trunk/brain_buster/
Have fun.
Homepage and repository are not accessible.
I've finally gotten this thing a public facing repository, and even added the license file (oops)...more updates coming soon.