A universal instant messaging (IM) program
See https://pidgin.im/about/ for more information. Pidgin is an instant messaging program which lets you log in to accounts on multiple chat networks simultaneously. It runs on Windows, Linux, and other UNIX operating systems. Pidgin is compatible with the following chat networks out of the box: AIM, ICQ, Google Talk, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, MXit, Novell GroupWise Messenger, Lotus Sametime, SILC, SIMPLE, MySpaceIM, and Zephyr. It is written in C and makes heavy use of GLib and GTK+. Finch is a command line instant messaging program. It also lets you log in to accounts on multiple chat network simultaneously, and it is compatible with the same chat networks as Pidgin. It is written in C and makes heavy use of GLib and ncurses.
A fork of pidgin which aims to provide minor features that have not been addressed by the pidgin development team (including manual textbox resizing). See funpidgin.sf.net for details.
Chirrup is a minimal XMPP client with a clear API, allowing for the easy development of multiple interfaces. All non-core functionality is implemented via plugins.
This is a plugin based jabber interface acts like a jabber client and listens to external commands in irc style. It is a remote shell with jabber being the command console.
Logging system for Jabberd2 written in Python and using the xmpp library.
Logtimes provides saving login events of your pidgin buddies, which makes you able to request the last login time of a buddy later on (e.g. to check whether your buddy has been online and read your messages within the last days). See Doc for details.
Froggie is an easy yet powerful Jabber multiplatform client. Jabber is a powerful open source instant messaging system.
Google Chat Client
The old google chat client (gTalk) had a nasty UI and looked old and needed a facelift and some additional plugins like Google Hangout support and Email in client itself.
xmppbox is a dropbox™/ubuntu-one™/mobileme™ like system implemented through the XMPP protocol, allowing users to exchange files, and sync up folders between computers.