I keep a two and a half foot piece of 1/2 inch rebar right inside the doorsill under the seat of my car, that way if anyone tries anything when i'm opening the door, they get rebar to the groin.
Back when I used to live in south minneapolis, and drove a hooptie Lincoln, I got that a lot. There are many street thugs who played too much GTA and didn't spend enough time at the gun range, that now spend an amazing amount of time in rehab.
The piece I used eventually developed a bend to it, good for aerodynamics, but after that it just lacked punch. Now I just tear their arms off.
~Brave Blue Mice