I'm wrapping up a chapter in my book on Unmanaged Interop this evening. In the process, I've fallen back in love with some classics on my bookshelf:
COM is still cool in my book. (Pun not intended.)
And furthermore, I can't tell you what a blessing it is to be able to write about a topic, encounter a question or two, and walk right down the hall to the guy's office who 1) knows the absolute most about a specific technology and 2) is kind enough to answer questions in exceeding detail. I hope this translates into a better end product.
Here are just a few (externally available) amazing resources related to hosting, CERs, and SafeHandles, the new face of Unmanaged Interop for V2.0: