I got an Escort 8500 X50 Rev. 6.1 blue for Christmas with this to keep it "safe."
It's made of 21 gauge steel thats painted black. It is 8.25"L x 6"W x 1.75" D and has a black foam lining on the inside. It came with a 31" coated "security" cable that has a loop on each end to secure the safe to your car. It had 2 hole pre-drilled to mount it, but I like being able to hide it under the seat or put it in my armrest console. I have the other end looped through the passenger seat fame. It came with 2 keys.
It is big enough to fit both my RD and PDA/GPS. I drive about 1,000 miles a week, with lots of stops where I am out of the car so I think using this isn't being too paranoid....or is it?