togelius writes: "What makes games fun? Some (e.g. Raph Koster) claim that is fun is learning — fun games are those which are easy to learn, but hard to master, with a long and smooth learning curve. I think we can create fun game rules automatically through measuring their learnability. In a recent experiment we do this using evolutionary computation, and create some simple Pacman-like new games completely without human intervention! Maybe this is the future for game design? (Blog post, paper)."