Scott Hanselman has posted a great list of questions that he believes all great .NET developers ought to know. It's a big list, it's a thorough list, it's a scary list! It's a great list to sharpen any .NET developers skills. Over the next couple of weeks I'm going to go through this list and make sure I know the answer to each of these questions. Then I will be a Great .NET Developer. 
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What a Great .NET Developer Ought to Know (More .NET Interview Questions)