One of the movies that innovated and popularized the horror comedy genre, 1984's Ghostbusters still stands up almost three decades later. When a paranormal poopstorm lands on New York City, the only people who can stop it are four brave ghost exterminators armed with proton packs and attitude. Ghostbusters is a classic because of a number of factors: great characters, sharp dialogue, incredible effects and a ton of imagination. Will we ever get Ghostbusters 3?