Kibitz is an Interface for the Free-Internet-Chess-Server (FICS) running natively under Mac OS X / Cocoa.
Features implemented in current (pre-alpha) version:
Playing and observing chess games on FICS
Observing multiple games
Chat with other users on FICS
Support for chess variants including “Bughouse” and “Crazyhouse”
Kibitz compiles as universal binary (support for Intel and PowerPC Macs). Kibitz is hosted at Berlios pages.