LogCabin is a distributed system that provides a small amount of highly replicated, consistent storage. It is a reliable place for other distributed systems to store their core metadata and is helpful in solving cluster management issues.
We've written a paper about the Raft consensus algorithm which LogCabin uses internally. A draft of this paper is available here (PDF).
The source code is here: https://github.com/logcabin/logcabin
Please report bugs and feature requests to https://github.com/logcabin/logcabin/issues . You'll need a github account (free) to submit new issues.
Other Raft Implementations
This information has moved to the Raft web page: http://raftconsensus.github.io
Paxos Made Live - An Engineering Perspective (PODC '07)
ZooKeeper (Yahoo!, Apache)
Paxos Made Simple (PODC '01)
See also Paxos Made Live under the Chubby heading.
Paxos Made Practical (not published, '07). Note: despite the title, this is actually about Viewstamped Replication, not Paxos.