Peerscape is an experimental peer-to-peer social network implemented as an extension to the Firefox web browser. It implements a kind of serverless read-write web supporting third-party AJAX application development.
Under the hood, your computer stores copies of your data, the data of your friends and the groups you have joined, and some data about, e.g., friends of friends. It also caches copies of other data that you navigate to. Computers that store the same data establish connections among themselves to keep it in sync.
It's all about managing information instead of servers. Peerscape uses public-key cryptographic signatures to encode the relationships among people, groups, and their content.
Peerscape is open source software available under the MIT License.
Go to Installation for information about obtaining and installing the software.
Then proceed to the instructions for getting started with the web interface.