Go Program Crazy Stone defeated Yoshio Ishida, a professional Go player

Interesting story. I spent a lot of free time in the late 1970s and early 1980s working on my Go playing program Honninbo Warrior (played poorly, but was the first commercial Go playing product).

The new Monte Carlo search technique (used by Crazy Stone) basically blows all previous approaches out of the water. I bought the "Championship Go" app for my android phone, it uses Monte Carlo, and plays well.