Speaking of vehicles, I have an air mattress in the back of my truck. My truck is a long bed, 8 feet long, and I keep the air mattress in there inflated at all times, unless I need to haul something. There's plenty of room between it and the tailgate to put over a dozen bags of groceries and it keeps them from sliding around. On top of the air mattress is a large duffel bag. Inside are my sleeping bag and insulated blanket that I use when camping. If my truck breaks down in the winter I can stay warm until help arrives. I also have a plastic tote in the truck all the time full of gear like a bow saw, tarps, bungee cords, and jumper cables. I've helped a lot of people jump start their cars but never my own. The air mattress keeps the box from sliding around. I have a first aid kit, flashlight, and toolkit in the cab too. I don't have any food or water in the truck but really should have a couple of bottles of water. I have a shovel that started out as a military surplus entrenching tool, and a hammer I made from a Vietnam tomahawk in the back too. Both have steel pipe handles welded on and could be deadly weapons. I use the hammer to set up my tent. I needed a hammer in the truck more than a tomahawk since I already keep a full size ax in there. If I had a passenger car I would carry most of those things in the trunk. You never know when you might need them.