Well, not really my first application, but the first that I'd show to the public. Its a simple die rolling program that can handle rolling multiple dice, multi-sided dice (meaning dice that don't have 6 sides, I know all dice are multi-sided), additive/subtractive dice rolls, and roll modifiers. I've not been able to test it on other machines, so if it doesn't work, let me know. It probably requires .NET 3.5 to be installed on your machine, but if your reading my blog, you probably have it already.
Example .NET 3.5 WPF Application
If any of you are wondering, dice rolling apps are my staple "hello world" app when learning a language/framework. They don't talk to a database (or at least this one doesn't), but they do involve string parsing, handling of arrays, visual layout, styling concerns, and "persistence" of settings when available (add some die rolls, close the app and open it again).