qGo is a full featured SGF editor and Go Client available for Linux, Windows and Mac. qGo is based on Qt 3.1+. qGo2, currently under development, will be based on Qt 4 and will be able to play go on IGS, WING, LGS, CyberORO, Tygem, Tom, and eWeiqi.
mojoPortal is an accessible, compliant, extensible, cross platform, cross database, content management system CMS written in C# ASP.NET. If you know how to make an ASP.NET UserControl then you already know how to make a feature that plugs into mojoPortal