Movies based on children's books by Dr. Seuss have done very well in Hollywood. How the Grinch Stole Christmas was a Jim Carrey blockbuster in 2000, as was the animated Horton Hears a Who in 2008. Mike Myers' The Cat in the Hat, on the other hand... well, two successful movies out of three ain't bad. But now that the news has broken that Universal will be releasing a 3D animated movie based on ecological parable The Lorax in 2012, one has to wonder how many movies ol' Theodor Geisel's oeuvre has left to give us. We looked over his body of work and called out some of the most marketable titles. Expect to see one or more of these in theatres by 2015.