Aba Daba
Aba Daba is a really nice version of the ancient game Gomoku. The objective of the game is to place five of your game pieces in a row, while the computer opponent tries to do the same. While this might sound easy, it actually requires quite some skill and strategy to win, especially on larger boards. Aba Daba supports five board sizes, eight skins, seven languages and three difficulty levels. Overall, the game is very nicely designed and really worth a look.
Version 1.31 adds support for some additional languages and fixes some bugs.
Alex the Allegator 2
Alex the Allegator 2 (spelled with an e) is a "gem." Although the graphics and sound are nice, the real impressive thing about this board game is its originality. I've never seen anything quite like it. In this game, your goal is to remove as many groups of tokens as possible. To remove tokens, simply create a group of same-colored tokens. This game has a high score table and the option to play single or two player. A quite enjoyable game. This game is best when played with a friend.
Arasan Chess
An very intelligent chess-playing program with many levels. You can play against the computer or you can choose to use Arasan with its console version that has Internet chess server support so you can play online. You can also let Arasan play on its own against other chess programs online, such as Crafty or Gnuchess. The graphic is basic, but that's not vital in this case when Arasan is equipped with such a powerful "brain".
Atakks
The nicest thing about this 2-player board game is the graphics and the animations of the markers. But without a regular game menu and other vitals, this game's value deflates quickly. The game rules are in French only. Note: If you need the required file SDL.DLL, it can be downloaded from the author's homepage.