The Monkeysphere is a system for using the OpenPGP web of trust in new areas. This add-on provides a framework to leverage the web of trust for authentication of HTTPS communications. This allows you to use your web browser to identify HTTPS-enabled websites through the OpenPGP Web of Trust. Everyone who has used a web browser has been interrupted by the "Are you sure you want to connect?" warning message, which occurs when the browser finds the site's certificate unacceptable. But web browser vendors (e.g. Microsoft or Mozilla) should not be responsible for determining whom (or what) the user trusts to certify the authenticity of a website, or the identity of another user online. The Monkeysphere project gives you an alternative. This extensions enables checking of X.509 certificates from HTTPS-enabled hosts whose keys are in the web of trust, providing you with a decentralized alternative mechanism for website validation.
This brings to the web the possibility for key transitions, transitive identifications, revocations, and expirations of public keys.