Railroad Ballast

These may look like just ordinary rocks. But when you spread them between train tracks, mere rocks become railroad ballast, which provides support and drainage. Carolina Sunrock sells Norfolk Southern Railwaymore than 150,000 tons of ballast a year, mostly traprock from one of its three quarries. The 200-employee company, based in Raleigh, North Carolina, is run by Bryan Pfohl, son of co-founder Joseph Pfohl.

Train Horn

Few things trigger as much nostalgia as the sound of a classic train horn. The gold standard in horns, and the one atop this Norfolk Southern train, is the Nathan Airchime P5, made by Micro Precision Group of South Windham, Connecticut. Robert Mongell founded the $8 million company in 1989, and it acquired the Nathan Airchime brand in 2003. The company makes 97 percent of the freight train horns sold in the U.S.

Tower Clock

Only two trains service the Hattiesburg train station each day, so passengers had best be on time. They get some help from this 5-foot-diameter clock made by the Electric Time Company, a Medfield, Massachusetts, business that has been making custom clocks since 1928. Donald Erb bought the company in 1969, and it's now run by his son Thomas. Electric Time's 40 employees handle more than 1,000 projects each year.

Ticket Kiosk

This historic train depot dates back to 1910, but don't expect to find a kindly old station agent manning the ticket window. Passengers must purchase tickets from a machine inside the station. The machine is made by Kiosk Information Systems of Louisville, Colorado. Founder Rick Malone designed electric toys before starting the company in 1993. Since then, Kiosk Information Systems has cranked out more than 100,000 machines for companies such as McDonald's and Wal-Mart.