Chessmaster 9000 Mac
[ $40 commercial] Grandmaster strength, many training features. OS X 10.2+ and DVD drive required. Released Dec. 2004.
Crafty 14.11B
[Freeware] Version of Crafty with code added so that ExaChess can be used as a GUI interface and computer-computer umpire.
Glaurung and Scatha
[Freeware] UCI GUI with two engines: Glaurung (normal chess), Scatha (Glinski's hexagonal chess), requires OSX 10.3.9+
HIARCS 10.0
[Commercial $40] Strongest Macintosh chess program, in UCI engine form for Mac OS/X. Can use endgame tablebases. [Out Dec. 13, 2005]
HIARCS 7.0
[Commercial - $48] Macintosh OS9/Classic version of a former world champion chess program.
MacChess - chess on Mac
Lists software for Mac OS X, classic, X11 and pre-OS X. Includes information for compiling and configuring X11 and XBoard based applications.
Sigma Chess 6.1.3 Lite
[Freeware] Free Macintosh chess program has 3D set, prints games with diagrams, includes HIARCS 10 demo, runs UCI chess engines. [ out Dec 29, 2005]