You can play against a "plugged-in" chess engine and use it for analysis.
With Scid you can maintain a database of chess games, search games by many criteria, view graphical trends...
Allows not only playing but also maintaining a database and analyzing games.
ExaChess is a powerful, full-featured chess-database program for the Macintosh.
Freeware, master strength Macintosh chess program for Mac OS X.
