Shareware
Aros Magic Checkers, Atlant Software, Jean-Bernard Alemanni's checkers programs, Serge Startsev
Buggy
Buggy is an international draughts (10x10, flying kings) program for windows. It is probably the strongest program for this checkers variant. Site available both in French and in English.
Checkers Games by Atlant Software
Game of checkers played against the PC. The programs contain self-learning algorithm of game and friendly interface.
Nemesis Checkers
Nemesis plays English/American checkers. It is the current computer checkers world champion.
Sage Draughts
Commercial checkers program, shareware version can be downloaded. Nice interface.
World Championship Checkers
English/American checkers program for windows.
Wyllie Checkers Program
English/American checkers program for windows, includes a large historic games archive.