Yes, another illusion, to add to this one, and to make a similar point, by what appear to be rather similar means:
The blue stripes do not slope. They merely look as if they slope.
I found this here. I recommend following that link and scrolling down to the .gif there, which proves that everything above really is horizontal.
Talking of horizontal, what happens if I do a horizontal slicing job? This is just the top blue stripe:
The trick still works, even if not as strikingly. Not that I care much about the details. That things like this work is what interests me.
Commenting on the previous illusion, Commenter Alastair recommended this book. It’s now on its way to me.