I love the story of the Seven Roach Rush. To quote the linked article, "The most interesting part of this build, however, is how counter-intuitive it is. It violates several well-known (and well-adhered-to) heuristics used by Starcraft players when creating builds."

I'm fairly certain that this application of machine learning will present some surprising strategies.

http://lbrandy.com/blog/2010/11/using-genetic-algorithms-to-...