CoolMoon is an implementation of mutual experience. It is a Firefox plugin to help with authentication. It is based on shared memory between browsers.

Traditional authentication methods are vulnerable to various kinds of false representation. CoolMoon avoids these approaches, providing a divergent and complementary method to recognize other people in cyberspace.

CoolMoon creates a coded binary string--bunch of ones and zeros--which preserves the essence of recent pages and sites viewed in a web browser. While it does not include any identifying information (such as domain names or text entered into an online form), this coded string makes sense to other web browsers and websites which use the CoolMoon method.