DAVID SAITO-CHUNG

Top-Rated Company Rock-Tenn's (RKT) business of paper packaging might not be as exciting as high-tech gadgets, robotic surgery systems or the like. But investors apparently are showing enthusiasm for the growing geography of markets it serves. The Norcross, Ga.-based company is a giant in corrugated and consumer packaging products as well as recycling services. Most of Rock-Tenn's sales — $5.4 billion in fiscal 2011 — hails from the U.S., Canada and Mexico. Rock-Tenn also serves markets in Chile,