When it comes to references and "secrets of" books, there are so many choices that it makes finding a decent book nearly impossible. I am delighted to have stumbled onto "Visual Basic Annotated Archives." Whether you need to learn how to write an ActiveX DLL or simply wish to look at snippets of clever code, this is the one to consider. I heard that one of the authors (Kent) is a teacher... it shows in his writing style, which is very easy to follow.