While driving north on California's picturesque Route 1 a few years ago, John Todd was not thinking about the magnificence of nature or the beauty of the landscape. Instead, he was wondering how anyone would know if his car veered off the steep cliff.

There was no cell phone or pager coverage in the area. Friends and family might only know that he was somewhere between Boston and San Francisco on one of his yearly cross-country excursions, he thought.

That prompted Todd to research tracking systems that can trace vehicle locations throughout the country. Dissatisfied with the options, hedecided to build a system of his own.

"It started out as an idea for just myself. But I think there is a really good market for companies and individuals that would find value in knowing where their cars or trucks are," said Todd, now chief executive of 10-20.com, a Laurel company that provides tracking services.

While there is no shortage of competitors, Todd said that 10-20.com is alone in its ability to track vehicles in the most rural parts of the nation. The company's system can even pinpoint a car deep in the mountains on an unmarked trail.

"We decided that there isn't any competition . . . offering this across the entire continent. They can offer it across a city or across the East Coast. But they all use a cell phone transport mechanism," Todd said. "We use two-way satellites, which is really the strong point."

The receiver is about the size of a small book and is powered by the car's battery. A small antenna on top of the car or truck sends signals to satellites, which identify the vehicle's location and mark it on a Web-based map. The equipment costs $995 and monthly service fees range from $20 to $65, depending on how often a location is updated.

Todd's team worked for nearly two years to develop the package and is now trying to build a customer base of individual consumers and small commercial companies.

10-20.com's Nick Avgerinos, left, and John Todd developed a vehicle-tracking system.