I use an old black nylon "range bag", stored in the back, secured under the elastic netting........for all practical purposes, not visible from outside the car. I must confess I feel better with my "junk" close at hand.

 

where can i get an aftermarket "secret compartment" for my R52?!?!? I am so jealous, I could really use that extra couple of inches of storage.

 

What's the biggest handgun that will fit in the secret compartment?

 

Not exactly secret, but the Euro Parcel Shelf is a great addition any first-gen MINI. I always keep my GPS, radar detector and sunglass case there when I'm not using them. There's a rubber mat that keeps things from sliding around or falling out, and most people that look inside your car don't think to look for things below the steering wheel. Here's a picture:

 

For small things that won't cut or abrade wiring, there are panels on either side of the boot in the sidewalls. The right side is big, in relative terms, and you can stuff quite a bit in if you're careful not to impinge upon the wires. The left side is not so large, but I've found things that will fit.

As for tire gage, I weave it through the mesh by the front passenger's left foot.