Captchas and anti-spam Gems

#Total RankDaily RankNameSummary
1604699recaptchaHelpers for the reCAPTCHA API
21,0791,797invisible_captchaUnobtrusive, flexible and complete spam protection for Rails applications using honeypo...
32,3161,966voight_kampffVoight-Kampff detects bots, spiders, crawlers and replicants
44,6345,278rakismetRakismet is the easiest way to integrate Akismet or TypePad's AntiSpam into your Rails ...