2D Board games
The tessera game is a "connect four" game. In it you have a vertical dashboard in which you put out pools. Your goal is to make a horizontal, vertical, or diagonal line of four of your pools.
The game is also known as: Plot Four, Find Four, Four in a Row, Four in a Line.
It can be played by two people on the same computer or one person against the computer (the level of "thinking" on the computer can be adjusted).
You can let the computer to play against itself. It's an interesting view. :)
* You can also read the article in Wikipedia: http://en.wikipedia.org/wiki/Connect_Four