I would like to bring to peoples attention a very good first person shooter game set in the old west, i.e cowboys and is called Smokin Guns, it is a totally free game that uses the quake 3 graphics engine so almost any computer will be powerful enough, if your computer is less than 10 years old then assume it will work good. It is available for windows and linux. This game is designed as a multiplayer game, the only way to play by yourself offline is against players controlled by the computer. I think it is a very well balanced game. There is a New Zealand based internet server to play on, all servers can be seen within the game but monster browser is recommended so you can see which servers contain human players rather than not knowing if the server has bots or humans before you connect to it.

youtube video showing gameplay - https://www.youtube.com/watch?v=RGIYZf-BBfA

Download the game - http://www.smokin-guns.org/downloads

Monster Browser download - https://sites.google.com/site/monsterbrowser/