title: What is a good sample class to demonstrate TDD?
body: <p>I need to give a short presentation (2-4 hours) on Test-Driven Development and need to come up with a small class that I can build using the TDD methodology.  The class has to be relatively small, but "sell" the concept of TDD.</p>
  
  <p>If anyone has read James Newkirk's book, Test-Driven Development for in Microsoft.Net, the Stack example is perfect.  It’s a small class, has a manageable list of tests/requirements, and the creation process sells TDD (IMHO).</p>
  
  <p>I don't want to use the Stack example or similar data structures (queue, lists, etc) for fear on impinging on Newkirk’s work.</p>
  
  <p>So, I’m looking for a few good ideas for a sample class.</p>
  
  <p>Thanks.</p>