Captcha
CAPTCHA: Completely Automated Public Turing test to tell Computers and Humans Apart
VouchSafe
VouchSafe is an easy, effective replacement for CAPTCHAs that requires users to simply draw a line to join two objects that are related, or to circle an object that doesn't belong in a collection. VouchSafe is the only Human Interactive Proof that uses a ...
On verify
TS Verification is a native joomla 1.5 plug-in, which is directly associated with one of the best verification system “On Verify” you would just need to install this plug-in to your site with your account details you have with “On Verify” and you are done ...
SweetCaptcha
SweetCaptcha is a free Captcha service putting your users and your website at first priority. No more quirky tilted text, no more form blockers, no more conversion rate droppers. Just 100% focus on design and a great user experience. Instead of aski ...
Picatcha
Picatcha (TM) is a unique image-identification CAPTCHA that effectively protects your website from Internet abuse - spam and automated bots. It is a well known fact that websites lose approximately 3-18% of user interactions (comments, sign-up etc) due to ...