Well, for me, anyway:
The Monster at the End of This Book, obviously, but also and more thrillingly
Duck Amuck, which you probably haven’t seen in far too long. But it’s on YouTube. Enjoy.
I have a strong feeling that the affection GenX obviously has for breaking-the-fourth-wall — e.g., Deadpool on page and filme — has at least some of its roots in these two documents.