Tower defense: very in. It would be neat to have such a game where competitors could write the code for defensive as well as offensive units in the manner of Robot Battle. Robot Battle had a stripped down programming language to code your robots.
The game price to purchase such a unit in the game would increase as lines of code increased. People could deposit their own creations for others to use in the game or keep certain ones for their own use, possibly in online competitions.
The price piece would be the great equalizer: I suspect some of the units in robot battle had many routines which they could use depending on the circumstances - total amount of code was not a consideration.
The heyday of robot battle was really before online gaming took root. I think maybe the time for this has come again. Or very possibly it already has come and I am not paying enough attention.-- bungston, Sep 23 2012 Robot Battle http://www.robotbattle.com/about.phpThis game had a predecessor for the Apple II as well. [bungston, Sep 23 2012] It should be called Hexadecimation because, if I recall correctly, the robot is oriented hexadecimally.-- rcarty, Sep 23 2012 random, halfbakery