Sumada Kaabaha: spambots
-
PRyC WP: AntiSPAM (without CAPTCHA)
Block SPAM without any type of CAPTCHA – plugin add "HoneyTrap" (and a few other tricks) for comment form to block SPAMbots.
-
ThreatPoint Email Validator
This plugin validates email in realtime using live connections and aggregated data, by leveraging the ThreatPoint email verification API service.