In RobotWar, players write programs in a language created specifically for the game, which is compiled down to a virtual machine code and then used as an AI for a (virtual) robot in arena battles against other players' robots.
It's currently a work in progress. I'll have installation instructions up soon, but in the meantime, if you'd like to create and email me some robot source code to test with, check out the following links to get started:
* [The original manual](http://corewar.co.uk/robotwar/robotwar.txt)
* [A blog post](http://www.filfre.net/2012/01/robot-war/) explaining the game in some detail
* Last but not least, an excellent [web-based JavaScript version](http://robotwarjs.net) that just came out.
You can easily use that last link to write and test robots. Both me and the guy who created that site are hewing pretty closely to the specs of the original game, so any robot code you create in his will almost certainly run in mine.
