Sente Goban
A program to play go on Mac OS X.
IGS client server, SGF editor, Standard GMP/GTP interface to computer go software. Local network play. Used to come with GNU Go preinstalled, now available by downloading an extension package.
Website: http://gobanapp.com/
July 2013: Version 4.2 includes the ability to play against Pachi.
June 2013: An updated version (4.0) appears on the Mac App Store.
The old, free version (3.2.12) is still available at https://www.macupdate.com/app/mac/8066/goban
May 2013: A message on their website says version 4.0 will soon appear on the App Store!
April 2012: Still no update since Nov 2007. Program is unstable under Mac OS X 10.6.8.
Nov 2010, [willemien} private email from author: The project is not abandoned, still hope to get more time to improve it.
2009: At this point, this appears to be abandonware, as it has not been updated since Nov 2007.