Caputchin

Caputchin replaces the usual CAPTCHA puzzle with a short game a visitor plays for a few seconds. The games need fast reactions with no answer readable from the page, and every round is re-checked on the server, so they are easy for people but keep out bots and AI solvers. It works without collecting any IP, fingerprint, or tracking data about your visitors, and the widget and games that run on your site are open source for developers to read and restyle.