Client for Game Masters (of a RPG) to control a Game session using Y! Messenger Protocol. This allows GM to talk to the whole group, a sub-group (or individual), etc. and helps her to have a centralized GUI, while players can connect normally to Y! Msgr.
Java Instant Message (IM) Library, Client and Tools. Flexible framework to design your own. AIM, ICQ, Yahoo, MSN, Jabber, SMS, Nate, GoogleTalk. GUI, spell checking and more. Includes a web interface for remote/cell access. Mac, Win, Linux friendly
JXTA Instant Messenger (J.I.M) is a project that aims to establish a server free, pure P2P Instant Messaging system. It is based on Java, JXTA (www.jxta.org) and the Java Cryptography Extension JCE and provides a nice Swing based GUI.