MasterGo

Was a commercial Go database program designed for searching patterns, such as when studying Fuseki and Joseki. The database contained 60132 professional games in a proprietary format (as of May 9 2015). Updates are (were) available to all registered users.

Main site: http://www.MasterGo.com/mastergo (dead link) http://hauenstein.nine.ch/mastergo/ (working link)

Distributors

The only known remaining distributor is Hebsacker Verlag

Direct link (in German): http://www.hebsacker-verlag.de/product_info.php?cPath=59_15&products_id=75

Reviews

see: Kombilo vs. Master Go