you know you can actually hide the key fob INSIDE the car, all you have to do is hide the key in a transparent aluminum bag aka static free bags. Hide the physically key around the car even behind the license plate screws and you're much safer since no one would ever think to look there when you have a push start car. Just saying. Physically key gets you in the door, and take the key out of the bag to start the car.

I'll add this as a disclaimer when I get the chance, but for the areas I run in, I've left my key in the car with the doors unlocked, and its still there when I get back (knock on wood). This isnt something I would use in an area I was unfamiliar with, but I feel better about using this hide-a-key idea than just putting the key on the tire, or anything else I've done.

You do know that you would get not a cent from you insurance if the car is stolen?
Why not do a belt-clip or sth. instead?
I have a spare key attached to the inside of my running-shirt while jogging and it works fine.