A power inverter is a small device that plugs into your car cigarette lighter and outputs electricity through a standard grounded socket, converting DC power from the car battery into AC 110-volt power just like you have in your house. You can plug literally anything into your power inverter: a blow dryer, air mattress pump, video game, cell phone, computer, etc.

It's great for on-the-go entertainment -- or for solving last-minute emergencies.