title: object oriented programming: looking for good tutorials
body: <p>I am tired of tutorials that just enumerate the concepts with examples. How about some tutorials that show the wrong way of doing and then the correct way of doing things? It would be great to learn things like interfaces, delegates, abstract classes, singleton ...etc that way. </p>
  
  <p>It would be great to read some clean code online as well but its hard to find...</p>
  
  <p>any recommendations??</p>
  
  <p>I develop in C# , .net , MS technologies...</p>