Stop a lot of spambots from polluting your site by making visitors identify a custom word displayed as an image before commenting.
BotSmasher stops spam by checking comments and registrations against the BotSmasher API.
Bloquea el spam de todo tipo de robots con un captcha que es invisible para los usuarios de tu web o blog.
Anti-Captcha is a transparent captcha solution which does not require any end-user interaction
Block users using blacklists domain from registering to your WordPress site.
The most advanced protection against sploggers and spam users registration, is fully WordPress, WordPress MU, BuddyPress and bbPress 2.0 compatible
A simple and efficient anti-spam plugin
Blue Captcha is a powerful and highly customized WordPress plugin that effectively protects your WP blogs from spammers and unwanted persons.
ZigTrap adds a honey trap to your comments form.
Unspam makes it harder for spammers to automatedly send spam to your blog by changing the names of the fields in the comment forms.
Kills spam dead in it's tracks. Be gone evil demon spam!
Dead simple and super lightweight anti-spambot WordPress plugin. No captcha, tricky questions or any other user interaction required at all.
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