Is there a good method of form security that does not involve CAPTCHA? CAPTCHA is so annoying, but I need security because I am getting form spam. My form is
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Math questions are interesting alternative. You can even write your own simple math checker by using random numbers.
Here are couple of plugins:
http://www.codegravity.com/projects/mathguard
http://sw-guide.de/wordpress/plugins/math-comment-spam-protection/