I've been meaning to add a blog entry for this for a while. It's just a link to my latest Code Project article that went live last week. It's a long piece describing a small library for handling the parsing of command line arguments in C# programs, either Console or GUI (there's a WPF example).
This is the first project I created using Test Driven Development so as well as the technical details of the library there's also a description of how I found TDD.
You can find it here: http://www.codeproject.com/KB/cs/NAttrArgs.aspx