Moyo Go Studio
Moyo Go Studio http://www.moyogo.com/ is a software program written by Frank de Groot.
For information about the controversies see the forum.
Though at some point in time it became free for distribution, Frank de Groot revoked the permission to re-distribute MoyoGo. See: http://www.lifein19x19.com/forum/viewtopic.php?t=3983&p=65841#p65841