IE6 and Windows Explorer
Both IE and Windows Explorer use most of the same code, the only -real- difference is that one is designed to interact with the internet, and the other is designed to interact with your hard drive. Most of it is in the same code base though, as such completely eliminating it is, as was stated, impossible. Really though it just shouldn't matter that much. If you don't like IE use something else, it's not like it takes up some massive amount of space or something.