GNU dico is a flexible dictionary server with a set of accompanying utilities. It supports a wide variety of dictionary database formats, ranging from the traditional "dict.org" databases up to Wikipedia format. Support for arbitrary new formats can be easily added using loadable modules. The dico library provides an API for writing new modules in C, Guile, or Python.
Syncless is an experimental, lightweight, non-blocking (asynchronous) client and server socket network communication library implemented in Stackless Python 2.6. It contains an asynchronous DNS resolver (using dnspython) and an HTTP server capable of serving WSGI applications. It aims to be a coroutine-based alternative of event-driven networking engines (such as Twisted and FriendFeed's Tornado). It is already about that fast, but it has fewer features and is less stable now.
jj is a simple FIFO and filesystem based Jabber/XMPP client. jj is inspired by the ii IRC client. jj is more tool than traditional instant messanger client. It can be easily extended with normal Unix tools. It is perfect for bots and notifications. Interaction with jj is done by writing and reading files from the server directory that jj creates.