A great amount of Pidgin's functionality is exposed through D-Bus, so you can do a lot with a script that uses D-Bus to communicate with a running Pidgin. D-Bus has bindings for many languages; this means you can write such a script in many languages including Python, Perl, C++, Java, Ruby, and Haskell.
The xmppclient module provides an xmpp thin client for drupal.
Brings all XMPP wonders to Drupal, interacting with user via javascript and plain old HTTP. Strophe javascript library is used for handling all javascript gears
Idavoll is an implementation of a generic publish-subscribe service component for Jabber servers, as described in JEP-0060
jabber chat interface to identi.ca