Saros is a Eclipse plugin for collaborative text editing that in particular targets distributed pair programming (also called remote pair programming), but can support arbitrarily many participants at once. All members of a session have an identical copy of an Eclipse project and Saros keeps these copies in sync as editing progresses.
Ibid is a multi-protocol, general purpose, instant messaging chat bot written in Python. It aims for a naturalistic interface rather than strict-syntax commands. Ibid understands many protocols, including IRC, Jabber/XMPP/Google Talk, Campfire, NMDC, and SILC. It also interacts over SMTP, HTTP, and various RPC protocols. Ibid aims to make plugins as easy as possible to write. It ships with a large collection of plugins for looking up information, performing conversions, storing factoids, delivering messages, and much more.
Scopserv Communicator is an audio/video Internet phone and instant messenger that supports some of the most popular VoIP and instant messaging protocols such as SIP, Jabber (XMPP), AIM/ICQ, MSN, Yahoo! Messenger, and a whole lot of other useful features. ScopServ Communicator is based on the SIP Communicator softphone.
JBuddy Messenger is an instant messaging client designed for everyday business use. It supports public instant messaging networks including AIM, ICQ, MSN, and Yahoo. With a paid license, JBuddy Messenger adds support for Google Talk, IBM Lotus Sametime, XMPP/Jabber, Microsoft Office Communications Server (OCS 2007) and Live Communications Server (LCS 2005), and the JBuddy Message Server. JBuddy Messenger offers the concept of a Meta-Buddy (Trillian calls them Meta Contacts), which is an aggregation of the presence of multiple screen names under one buddy. Also, buddy groups of the same name across multiple accounts can be visually merged to simplify large buddy lists.