Lane Signals

These LED traffic lights, which are housed in aluminum, connect to the toll plaza's central computer. General Traffic Equipment, of Newburgh, New York, sells these signals to municipalities across the nation, to the tune of $2.5 million last year. Raymond Staffon, who started the company, in 1981, also markets its product line to department stores and other businesses that want to create indoor street scenes. The company employs about 20 people.

Axle-Counting Treadles

Embedded in the pavement are treadles--8-foot strips that count the number of axles that drive over them. That number helps determine the toll (a five-axle semi traveling through this location, for instance, would pay $2.50). The treadles, made by TRMI, in Accord, New York, account for both forward and reverse crossings, so that when a car backs up, the axles aren't counted twice. When Bob Rosakranse founded TRMI, in 1974, treadles were his only product. The $8 million company now makes a breadth of equipment for toll plazas, including automatic coin machines and receipt printers. It employs 45 people.

Cashless Toll Collection

With the E-ZPass system, there's no need to fumble for change. This antenna, made by Mark IV Industries, uses radio-frequency identification, or RFID, technology to scan a small device attached to a car's windshield, and a toll gets docked from the driver's account. More than 3,000 toll lanes in 12 states now use E-ZPass. Mark IV Industries, an Amherst, New York, company that was founded by Salvatore Alfiero in 1969, began as a maker of mobile homes. Then Alfiero went on a buying binge, and one of the more than 40 companies he acquired had developed the E-ZPass technology. These days, Mark IV generates more than $1 billion a year and employs 6,000 people. It is owned by a private equity firm.

License-Plate Cameras

Toll dodgers, beware: You're being watched by these cameras from Transport Data Systems, (TDS) in San Diego. When a car passes through the lane, the cameras snap photos of the license plates. If you don't pay, the images get sent to the ominously named Violation Processing Center, which grabs your information from your state DMV and mails you a fine. CEO Dick Hasselbring started TDS, in 1995, to market an invention that uses radar to distinguish cars from trucks at tollbooths. Today TDS, with a staff of four, brings in more than $1 million a year.