Salut à Toi (or SàT: "Hi to You") is an XMPP/Jabber client with multi-frontends. You can use it on a desktop (Wix), with a console interface (Primitivus), as a command-line tool (jp), or on the Web (Libervia). A plugin architecture is used to make it modular. With SàT, you can perform all the expected XMPP functions (instant messaging, multi-user chat, file transfert, etc.), but you can also use your email client (MUA) to read and send your XMPP messages, play games, do microblogging, pipe Unix command results, make scripts, etc.
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.