Gabber is a Jabber client for GNOME. Jabber is a flexible distributed Open Source instant messaging system. It also happens to allow communication with other instant messaging systems, such as ICQ, AIM, Yahoo!, MSN, and even IRC. Gabber aims to implement quite a bit of Jabber's functionality while remaining easy to use.
pork is an ncurses-based AOL instant messenger client. It uses the OSCAR protocol (the one the Windows client uses) to access AIM. Pork features Perl scripting, an online help system, the ability to configure nearly all aspects of the program's look and feel, an alias system, and a powerful, fully configurable key binding system. It supports being logged in with more than one screen name at the same time. The default look and feel of the client is modeled after the ircII IRC client. Anyone comfortable using ircII (or any clients derived from it, e.g. epic, BitchX, etc.) will feel comfortable using pork.