Kind of a spin off of the seat belt post. I don't think I've seen this topic before.
Do you have a bunch of stuff in your car that is unsecured? They can become deadly projectiles. Even that soda can, your cell phone, CD's, your purse, etc.
I had a girlfriend who was in an accident a few years ago, as a backseat passenger. She was hit in the face with a cell phone, it broke her nose. Luckily nothing worse. But imagine if that was an infant or young child, the damages could have been way worse.