At the Homebrew Computer Club Reunion, I learned that there's the possibility of Jef Raskin's human interface ideas as realized in the Canon Cat will become available to a wider audience through an emulation project at archive.org. I'm not certain, but I believe that it's the TOSEC project.
Further, when looking this up today, I learned that Jef was using Python himself to implement his interface concepts. Unfortunately, raskincenter.org is gone today, the inhabited url by a camper. I'm sure the work is out there somewhere, but presently I'd have more interest in what Aza Raskin is up to, as he seems to be doing a fine job of carrying on.