For every book that's been made into a film, there are thousands just waiting in literature limbo for someone to give them some cinematic love. There are some good suggestions made here. I have always thought that A Confederacy of Dunces would make an excellent film and I heard somewhere that John Candy was considering making the film and casting himself as Ignatius. I also think Oryx and Crake would translate well to the screen.
See more at this Link Via Nag on the Lake