Bernie Gunther
Fundamentalist Druid
Cities of the Red Night by William Burroughs
It would be impossible to do of course, but I would like to see someone have a shot at it
I thought Naked Lunch would be impossible, but Cronenberg pulled it off rather well (although he was, by his own account, making a movie of the halluncinations Burroughs was having when he wrote the book rather than the book itself)
What about Nova Express? There was some sort of attempt in the 60's that Paul McCartney of all people put up funding for and I believe Donald Cammel was involved or potentially involved, but as far as I know it never got anywhere.
That'd be a real challenge I think ...