Cactus Comments is a federated comment system for the web, based on the Matrix protocol.
A new wire protocol enabling applications to connect privately in a real-time and fully distributed manner, freeing them from relying on centralized datacenters
Storm now has a website!
Powerhose is a single master/ multiple worker zmq lib, that can be used to push some work to specialized workers.
Fossil: Simple, high-reliability, distributed software configuration management ... with bug/issue tracker, wiki, web interface etc.
The best features of document databases, key/values stores, and RDBMSes in one.
Mongo (from "humongous") is a high-performance, open source, schema-free document-oriented database.
TestSwarm provides distributed continuous integration testing for JavaScript. It was initially created by John Resig as a tool to support the jQuery project and has since moved to become an official Mozilla Labs project.