Quick little arithmetic plain-text captcha

Forked from https://github.com/kares/simple_captcha

Description of RailsCaptcha.

Anti-spam protection for your website

jQuery slide captcha system with jQuery & jQuery UI for Rails 3

Simple captcha image generator gem

Solve Media CAPTCHA Replacement

Captcha generator for rails

Define questions and answers in a YAML file and validate your models with a single line of code. No more captchas or other stupid tricks.

Merb plugin that provides resource access rate limits and captcha'ing

Generates Text Catpchas, that are 'nice' by my own personal definition!

ALTCHA is a free, open-source CAPTCHA alternative that protects your website from spam and abuse

This gem enable to use Captchme. Anti spam, Monetize captcha and Audience qualification

Block repetetive requests from logged_in users and shows captcha.

Repackaged visualCaptcha's backend service, including translation and minor modification. Mainly for private use. Everything still belongs to original author: emotionLoop. ...

Ruby port of VIT AutoCaptcha

This version include two important page 'Contact' and 'Register' with the 'Math-Captcha' method submit for prevent hacker attack.

Russian Post tracking toolset, consisting tracking form bot (since Russian Post is too retarded for normal API) and captcha solver/recognizer.

Easy to use classical captcha for Rails apps

To help with keep the bots at bay this gem helps you easily add honeypots to forms and/or obfuscate your form field names