Yeah, great thread lol. I feel compelled to contribute:
I keep my Jeep Rubicon's insurance papers under the carpet in the trunk. My Rubicon's been broken into half a dozen times. The glove box gets rooted through every time. They've NEVER stolen my insurance papers (with my name, address etc) because...(wait for it)...they were hidden in the trunk.
Yes, there is the inconvenience of retrieving the papers from the trunk if I'm pulled over, but the cops always say they understand why I hide them.
...and I understand why they stand back with their hands on their guns when I start rooting around in the trunk