Captchas and anti-spam Gems

#Total RankDaily RankNameSummary
1785563recaptchaHelpers for the reCAPTCHA API
21,822806invisible_captchaUnobtrusive, flexible and simple spam protection for Rails applications using honeypot ...
32,3031,619voight_kampffVoight-Kampff detects bots, spiders, crawlers and replicants
43,5294,359rakismetRakismet is the easiest way to integrate Akismet or TypePad's AntiSpam into your Rails ...