CAPTCHA alternatives

If your web forms are getting spammed, and CAPTCHA isn’t a good solution, here are some possible alternatives.

• http://isc.sans.org/diary.html?storyid=1836
• http://softwareas.com/captcha-alternatives-and-end-user-attitudes
• I’ve taken to renaming our feedback pages, and then using robots.txt to prevent search engines from indexing their new names.

• Related Link: http://kb.ucla.edu/articles/view/what-is-captcha

The Akismet service has a good reputation, and is widely used by Wordpress amongst others. It could be another layer of protection against spam.

• http://akismet.com/ (official site)
• http://codex.wordpress.org/Akismet (an example of it in a blogcentric CMS)