playbox.fx

Playbox.fx is a free, ad-free and still growing collection of board games. It is a private hobby project with no commercial goals.
It contains Mahjong Solitaire, Draughts, Chess, Go, Halma, Nine Men's Morris and Peg Solitaire. The games can be played against a simple AI or locally against friends. There is a portable version (zip) for Linux. There is an installer (exe) and a portable version (zip) for Windows.

Have fun and stay healthy, Markus.