Dear Steve,
In the current Mark Twain Annual, Derek Royal has a terrific piece on all
the comic book treatments of Twain, as well as some of the odder graphic
representations of his work out there in cyberspace. They are not all
"spinoffs" but they're really interesting appropriations and interpretations
of his work.
Hope that helps!
Ann
Ann M. Ryan
The Mark Twain Annual, Editor
Associate Professor
Department of English
Le Moyne College
Syracuse NY 13214