This is a go client program I wrote to experiment with unusual rulesets. Its most unusual feature is its support for more than two players. I used this program to play the Three Colour Ongoing Game.
It also exports sharp-looking PostScript diagrams.
Watch out! The program hasn't been maintained or updated in several years.
The program is under Bazaar revision control. To get a copy, do
bzr get http://www.bamsoftware.com/bzr/goclient