Adium is a fast and free instant messaging client which supports AIM, ICQ, Jabber, MSN, Yahoo!, Google Talk, Yahoo! Japan, Bonjour, Gadu-Gadu, Novell Groupwise, and Lotus Sametime. Adium supports beautiful WebKit message display, tabbed messaging, encrypted chat, file transfer, and more. Give it a try; you won't look back.
Significantly for users with disabilities, the Adium X version 1.2 is now properly accessible to VoiceOver so you won't have to guess who you're talking to. The Adium team care about accessibility - when I asked on IRC about making the text bigger to help with my low vision issues, several people were patient and helpful.
Adium X is a free program! I highly recommend it to people interested in text chat / instant messaging.
- Ricky Buchanan