Anthony Burgess really opened my eyes to tons (tonnes) of new words. Like so many, I started with A Clockwork Orange (and like so many, I read the whole thing without realizing their was a Nadsat glossary in the back!). I find it fascinating that so many of his invented words from that book have entered the language. In Earthly Powers, I'm convinced that he put at least one word that needed looking up on each page (sibilant and steatopygous immediately come to mind). A hell of a way to get through a book, but I muddled through, eventually. I owe him a great debt, as he was my first introduction to the amazing possibilities of language.