A buddy of mine had his cat stolen recently in the SF bay area which gave me an idea.  I park my truck on a dirt area on the side of my driveway.  It has tiny wood chips all around (ideal for night time camo).  I'm thinking of welding up a bunch of 'jacks' (like kids play with) from some small steel rod and then sharpening the ends.  Figure I'd throw them under the center of the truck and if these jokers try to get to my junk they will get a small surprise. I'll just have to use caution not to puncture my tires when backing up but hey nothing is easy.