Scid vs. PC 4.19

Scid vs. PC is a continuation of Shane's Chess Information Database, which provides a chess toolkit, move database, analysis tools, various chess AI engine bindings or to online servers. It remains database-compatible but adds many usability and feature enhancements, such as a tournament game mode, an overhauled GUI, new gamelists, rating graphs, other analysis engines, and drag and drop support on all platforms.

Gambit 1.0.3

Gambit is a graphical chess game. It's cross-platform and there are binaries for Windows, and build instructions for Linux users.