A game ideally suited to the OLPC laptop is tank game Bolo.
Here are some reasons why it would make a good addition:
- It was originally developed on the Macintosh 25 years ago and has low system requirements;
- The network requirements are ideally suited to the mesh network of the OLPC;
- There is already a linux verion;
- Has a simple, intuitive interface; and
- It's great fun.
For details see the wikipedia entry: http://en.wikipedia.org/wiki/Bolo_(computer_game)