GNU Shogi
The standard Shogi free software. Often used as an reference in Shogi program conpetitions. (Requires xshogi for a GUI)
GNU xshogi
A GUI for Shogi-playing software (GNU Shogi and the Internet Shogi Server, in particular).
Shogi Software
Contains downloads for Shogi games for Windows and Windows 98.
Shogi Variants
A Windows program for playing a variety of ancient variations on Shogi, from the smallest, to the largest.