Confident Technologies provides free CAPTCHA security software called Confident CAPTCHA, a picture CAPTCHA that stops spam and ...

Solve Media's CAPTCHA TYPE-IN ads are an easy plug-in solution that saves your users time while making your site more secure a ...

Open-source implementation of server-side spam filtering of blog comments and forum posts. It's available as a free web servic ...

A spam filtering program that is free for personal use and you have to pay for corporate usage.

A negative captcha has the exact same purpose as your run-of-the-mill image captcha: To keep bots from submitting forms. Image ...

Spam protection plugins for Joomla, WordPress, phpBB3, IP.Board, vBulletin and etc. Protection without CAPTCHA.

What Does NoMoreCaptchas Do? NoMoreCaptchas stops bots that try to register and log in to websites, leave spam comments on blo ...

reCAPTCHA is a free CAPTCHA service that helps to digitize books, newspapers and old time radio shows. About 200 million CAPTC ...

UniqPin is a free for non-commercial use service which destiny improve ability of interfaces detect a human or a computer oper ...

visualCaptcha is a configurable captcha solution, focusing on accessibility & simplicity, whilst maintaining security. It' ...