Will consum ers trade lower prices for less privacy? Car owners now can let insurance companies m onitor their driving, using a new technology, in exchange for lower rates. Customers who sign up for Progressive's TripSense program get a device the size of a Tic Tac box to plug into their cars. The device tracks speed and how many miles are driven at what times of day. Every few months, customers unplug the device from the car, plug it into a computer, download the data, and send the data to the company.

D epending on results, discounts will range from