Trial Balance is a simple accounting application, designed as a learning tool to teach basic double-entry accounting to high school and university students. It is created in C# on the .NET 2.0 platform. The user interface is built upon Windows Presentation Foundation in XAML.
The source code is actually hosted on our SVN repository here at Fuel Advance:
http://firstname.lastname@example.org/hosted/trialbalance (the original codename was "Banana" until Paul actually told me what I was hosting)