Isn't this type of image often called the "Moebius Effect"? Try searching for that term. I think I have seen a couple of tutorials on the process. One of them may have been at Strukwurk's site....

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Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.