Back when I was at school, I remember tinkering with a Mac game where you programmed little robots in a sort of pseudo-assembler language which could then battle each other. They could move themselves around the arena, look for opponents in different directions, and fire some sort of weapon. Pretty basic stuff, but I remember it quite fondly, even if I can't remember the name.
Are there any good modern day equivalents?
Just found Light Bot. Program your robot to move around and perform tasks to complete a puzzle. Even includes subroutines. Program the bot by dragging tiles into slots. The game is very polished.
Update Lightbot is now the most recent version of the game, and has versions specifically designed for kids ages 4-8 or ages 9+ (with no upper limit) and also features kind of an if
screen of lightbot 1 http://www.lostateminor.com/wp-content/uploads/2008/10/light-bot.jpg
If you want to step away from your keyboard, Wizards of the Coast relased a game called RoboRally that is a combative programming board game.
http://www.wizards.com/roborally/
You must be thinking of RoboWar. Oh how lovely it is.
Still exists, though the community is slowly dying.
http://robowar.sourceforge.net/RoboWar5/index.html http://tech.groups.yahoo.com/group/robowar/
Another good one is CEEBot. It teaches C / Java style programming in a fun, robot-programming kind of game. It is aimed at 10-15 year olds, but it is a good one.
I used to have a lot of fun coding my own robot with Robocode in college.
It is Java based, the API is detailled and it's pretty easy to get a challenging robot up and running.
Here is an example :
A game in which you have to graphically construct and train artificial neural networks in order to control a bug is Bug Brain.
Bug Brain screen shot http://www.infionline.net/~wtnewton/oldcomp/bugbrain.jpg