I was teaching a computer how to play chess. It was part of a science fair activity that we hosted in our home each week, where guests would be aligned into groups and set to solving some science (usually physics) problem via experimentation. My chess routine was much more clever than I'd originally intended, it turned out; it devised a better method of notation than any of the existing ones and started developing some bizarre strategies that were extremely aggressive but exploited human psychology very well. It got so good at violently overthrowing the game that I eventually sold it to the US military, in conjunction with a satellite network for targeting a variety of weapon systems. The big demo was to be in Florence, Italy but unfortunately the place I rented was very old and it turned out not to have any grounded outlets, so none of the high-power equipment would work.