With consumer credit ratings plummeting, more American car owners could soon be driving around with an electronic Big Brother on board.

Business is booming for makers of shut-off devices, which turn engines off when car payments are late. Sales at one manufacturer, Littleton, Colorado-based Passtime, are up 33 percent over last year. CEO Stan Schwarz says the company is cranking up production to meet the demand…

While the devices have mostly been used in the subprime auto loan market, other lenders are looking closely at the technology, manufacturers say. It’s no mystery why interest in the gadgets soaring: the creditworthiness of American consumers is declining as they lose jobs in record numbers and find it harder to tap into home equity…

Consumers could increasingly find themselves in cars with shut-off devices if their credit turns bad and they are forced to shop at dealerships serving the subprime market. These sellers range from small mom-and-pop, “Buy Here, Finance Here” outlets to major dealerships…

The products also include global positioning, or GPS, to speed up the repossession of the vehicle, if necessary.

I still wouldn’t want to be the guy who shows up to repo the car.