Disclaimer.....I would suggest you get a carry permit for this setup. Depending on the circumstances, and where you're driving, this mod could cause some legal troubles, if uncovered. So do it at your own risk.
A loaded gun in your car is worthless, unless you can get to it quickly in an emergency. Car-jackings are a frequent occurrence in St Louis. Let him have the car you say? In St Louis, after you give up your car at gun-point, you are often shot to death anyway. This mod gives you a chance to live....if you find yourself a victim.
You need a small gun to be totally stealth.....my Baretta .25 is a good choice. It fits in my pocket, or in this Pepsi bottle. If you're left-handed, learn to shoot as a right-hander. As you exit the car, pull up the Pepsi bottle about 4-5" with your left hand. The handle of the Baretta is exposed, and you're ready to defend yourself in a flash.
I used a round foam disk covered with black felt, and glued it inside the bottle. The thing looks like an opened bottle of soda.....and the gun is completely hidden from a casual observer. I lined the bottom inside of the bottle with felt, and covered the edges with black duct tape....to keep from scratching the gun finish. This project took about 1/2 hr.....and might save my life.