SoaringSimpleCaptcha is available to be used with Rails 3 or above and also it provides the backward compatibility with previous versions of Rails.

这是一个验证码生成器。基于rucaptcha。本人只是将他的源码拉下来。为我的网站进行适配。因为我不使用sesion.id

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

Metabypass | Ruby-based easy implementation for solving any type of captcha by Metabypass

0-9 arası sayıları kullanarak random olarak 2 sayı seçer ve yine random olarak toplama ya da çarpma yaparak sonucu verir.

Solve Media CAPTCHA Replacement

Integrate the AreYouAHuman.com CAPTCHA alternative human verification into your Ruby/Rails application

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

Simple captcha image generator gem

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

create captcha for api based project

This is a gem wrapper for tiny captcha in C with no dependencies.

This is mt first gem

A simple and fast image captcha generator that uses opencv and memcached.

Description of TinyCaptcha.

A gem to generate captcha pictures.

This library can help you create a captcha in your terminal application, which may be damaged by a large influx of requests.

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