Finch is a console-based IM program that lets you sign on to AIM, Jabber, MSN, Yahoo!, and other IM networks. It runs on Unixes. It uses GLib and ncurses.
License: Open Source
Pidgin is a versatile multi-protocol instant messaging client with a graphical interface, making it suitable for general users. Finch, on the other hand, is a lightweight command-line client best suited for advanced users who prefer speed and efficiency in terminal environments.