Slug Go

SlugGo is a shell over GNU Go that adds global search to GNU Go's local evaluations. SlugGo runs on a cluster of Macintosh computers, and each CPU in the cluster does an independent lookahead. Candidate moves for lookahead are determined based upon a weighted mix of GNU Go's standard evaluation, additional evaluation by GNU Go functions, and an algorithm that implements a varient of the Go proverb "Your opponent's move is your own." For SlugGo it is more like "pay attention to where your opponent would like to move." Results from the independent lookahead paths are collected at a master node to decide upon the move to be played. Depending upon the branching factor of the global lookahead, SlugGo may use as few as a dozen CPUs, or as many as 96. Careful analysis of games showed that this methodology did not scale well beyond about 24 CPUs for opponents other than standard GNU Go.

More info about SlugGo (including a paper presented at the 3rd ICOB) was once available at: http://sluggo.dforge.cse.ucsc.edu/