Captchas and anti-spam Gems

#Total RankDaily RankNameSummary
1659365recaptchaHelpers for the reCAPTCHA API
21,093689invisible_captchaUnobtrusive, flexible and complete spam protection for Rails applications using honeypo...
32,2742,222voight_kampffVoight-Kampff detects bots, spiders, crawlers and replicants
44,5315,162rakismetRakismet is the easiest way to integrate Akismet or TypePad's AntiSpam into your Rails ...