Which Sci-Fi, Fantasy and/or Horror Novel NEEDS to be Adapted?

As movie geeks, we all have our opinions on virtually every aspect of the motion pictures universe. Now, its time for us to share some of those opinions … on one, very specific but fascinating (often controversial) portion of the massive beast known as THE MOVIES. Many films have been adapted from books, dating all the way back to the origins of the movies, and the trend continues as strong as ever. Now, I ask the question … what sci-fi, fantasy and/or horror novel NEEDS to be made into a movie? [There are lots of books out there, so I’ve narrowed the genre to select from.] Personally, I’ve wanted to see Terry Pratchett and Neil Gaiman’s classic Good Omens adapted into a movie for a long time. You can imagine how exciting  I was the entire time Terry Gilliam was rumored to be developing the project, until I learned it was dropped. Dangit! On a related note, I think it’d be really cool to see Neil Gaiman’s American Gods adapted for the big screen. [Can you tell I’m a fan?] So … tell us what you’re pick would be.