I've been a Stephen King fan since high school. I view him as a kind of folk hero, and one of the people I would most like to be. I have a Stephen King-esque novel that I wrote and that really needs a re-write and another round of rejection letters someday.
I've read about 2/3rds of his stuff probably. The most famous novel of his that I've never read would be "It". The most recent of his that I've read was "Duma Key", I really liked it. I've been meaning to read "Under the Dome" but I'd need a substantial chunk of time set aside to do it since it's so big. I bought and read each of the Dark Tower books as they were released with the exception of the first two. My favorite obscure book of his is probably "The Regulators".