Tired of people breaking into your car to take things, while you're not able to properly hide things in the back seat? Drape a moving blanket covered in trash over the stuff you want to hide. People who might otherwise break in will just think your car is filled with trash and that some depressed and mentally ill person lives there.

All it takes is a moving blanket, and a bunch of chip bags, candy wrappers, fast food containers, empty drink cans, cigarette butts, used brown paper bags, rumpled tissue paper, and other random debris which you attach to the blanket using hot glue or staples. Just make sure your coverage is complete enough where nobody can see the blanket underneath the layer of trash. Drape this over whatever's in your back seat.