Captchas and anti-spam Gems

#Total RankDaily RankNameSummary
1723535recaptchaHelpers for the reCAPTCHA API
21,2271,090invisible_captchaUnobtrusive, flexible and complete spam protection for Rails applications using honeypo...
32,2422,200voight_kampffVoight-Kampff detects bots, spiders, crawlers and replicants
44,0654,741rakismetRakismet is the easiest way to integrate Akismet or TypePad's AntiSpam into your Rails ...