Six airbags are now standard in almost all cars in Europe, and eight is not uncommon. An additional airbag could soon be added. And one for the feet. ZF Lifetec has developed the Active Heel Airbag.

NEW YORK (CNNMoney.com) -- It used to be horsepower. Then it was fuel economy. Now there's another number making its way into the big print in car ads: the number of airbags. Already, Toyota is ...