Captchas and anti-spam Gems

#Total RankDaily RankNameSummary
1699465recaptchaHelpers for the reCAPTCHA API
21,1781,065invisible_captchaUnobtrusive, flexible and complete spam protection for Rails applications using honeypo...
32,2501,993voight_kampffVoight-Kampff detects bots, spiders, crawlers and replicants
44,2454,860rakismetRakismet is the easiest way to integrate Akismet or TypePad's AntiSpam into your Rails ...