We are proud to announce that the whole source code and documentation about our "lego robot playing draughts" is on Google Code, exactly here.
The software has been written in Java, using leJOS API for controlling the NXT Brick.
It is possible to use Java by flashing a custom firmware on it.
It has been a great chance to improve our programming knowledge in Java (in source code you'll find a lot of code as implementation of threading, class factories, interfaces) and have fun.