Here is some irony; the average Philadelphian drives only half the distance that the their suburban counterparts drive (11 miles per day per capita vs. 24 in the surrounding counties), yet city insurance premiums can be up to 50% higher.
PAYD or Pay As You Drive Insurance. It bases insurance costs on the miles or the time that you are driving. Environmental Defense estimates that universal PAYD insurance would reduce congestion and vehicle miles traveled by 10 to 12 percent.
GMAC and OnStar customers in Pennsylvania offer PAYD on new cars in Pennsylvania equipped with the OnStar system. It's reported that those who drive less than 15K per year receivee a 15% discount while those who drive less than 2500 miles receive up to a 35% discount.