UCI chess engine
Sunfish: a Python Chess Engine in 111 lines of code
Chess training program playing gambits
ChessMD is a Qt-based chess game viewer with engine analysis
Chess engine written in Pascal with an UCI interface.
Chess Database and PGN viewer
maXbox is a script tool engine, compiler and source lib all in one exe
Delphi Java - VRCalc++ OOSL (Script) and + (Binary Exec Distro)
Delphi : VRCalc++ OOSL & + (Paged List, TextEditor, VRAstroVision ...)
A collection of patches for the upstream Scid vs PC project.
A work-in-progress chess bot written in C#
NetChess to play between two players over net or internet
Chess program
Python chess engine
SJCE - free portable cross-platform graphical chess game, 100% Java.
The forever free, ad-free and open source chess server
EXCEL VBA chess engine with chess board
Extensive Java chess database libraries.
Chess Database application