Philip (one of my genius nephews) and I (not a genius) collaborated on one of his school projects. He wanted to learn C# and asked me to be his mentor. Since we have a lot of family members who are interested in genealogy, I thought it would be fun to work on an ancestry tool. So, together we built a Windows Forms application (written in C#) that allows you to specify a family tree. The application reads from and writes to an XML file, which stores the ancestry information. The XML file must be specified each time you start the application.
Philip is hosting the executable and initial XML file here, along with limited documentation. The Microsoft .NET Framework 2.0 is required to run the application.