I've never been a big fan of chess - mainly because I'm useless at it - but this is one chess game that doesn't ruin things by trying to be too flashy or original.
Arasan is an excellent but simple option for those who don't want to pay for a highly intelligent and feature packed commercial chess game.
What impresses, for a free chess game of it's nature, is the fact the Artificial Intelligence of the computer opponent which is remarkably good.
It seems to be able to change itself according to your ability and of course, is always that one bit better. In which case, you might want to play against a friend which you can do online.
You can save games in PGN format which means that you can review your greatest victories or look at where you went wrong. Arasan has both a native Windows user interface and a console-based chess engine for use with Winboard or xboard.
Arasan also works with Arena, which is another free chess interface, and with UCI-compatible programs like Shredder. However, those that have used the program over long periods of time have reported on forums that it does tend to repeat moves and positions after a while although this latest release has sought to address this.