SJCE - free portable cross-platform graphical chess game, 100% Java.
Python chess engine
Chess Database Application
A console/ncurses chess engine frontend and PGN editor.
Logical game
The forever free, ad-free and open source chess server
A two-dimensional classic game of Chess.
A cross-platform chess game.
Basic console interface for 3 player chess in a 7x7x7 cube.
A JavaScript game library to quickly develop board games for the web
Chess Database application
EXCEL VBA chess engine with chess board
Extensive Java chess database libraries.
Sunsetter, a chess, crazyhouse, and bughouse playing program
Java Chess Engine