Captchas and anti-spam Gems

#Total RankDaily RankNameSummary
1706544recaptchaHelpers for the reCAPTCHA API
21,1931,200invisible_captchaUnobtrusive, flexible and complete spam protection for Rails applications using honeypo...
32,2732,172voight_kampffVoight-Kampff detects bots, spiders, crawlers and replicants
44,1544,146rakismetRakismet is the easiest way to integrate Akismet or TypePad's AntiSpam into your Rails ...