Virtual Toll: Pay Per Mile Drivers are Less Likely To Drive

....... motorists' behavior might change if they had to pay tolls — not just on a few bridges or highways, but on almost every road with a yellow center line.

Researchers established virtual tolls ranging from a nickel to 50 cents a mile. They gave participants pre-paid accounts of between $600 and $3,000, and told them they could keep whatever the tolls didn't eat up.

The experiment ended in February. Preliminary results, released this month, suggest that if such so-called "road pricing" were widespread, it could make a significant dent in traffic.