About 4 years ago, my car was in aparking garage at my old employers office. Well, I got back from the field one night, pretty late (close to 9 PM, if I remember) and foudn a kid prying the EX and CIVIC emblems off my car. Funn enough, he didn't hear me coming and i gave him a kick between the legs (and from behind hurts the worse!!!!!!!!!!)
Needless to say, after beating the hell out of him for a mintue or so, I let him go. I let him keep the emblems, but I told him if he came back into the garage, I'd brutally torture him and toss his body in a dumpster. I don't think he ever came back.
I believe thieves should be punished brutally. If you can't work for what you want, you don't deserve it.