A friend of mine who used to live in East Van got tired of people breaking into his car for nothing. He decided to do a little experiment:
He put a little sticker on his window that reads "Dear thief, driver's door is unlocked. Please use it for your safety and convenience" and see if anyone would still be interested in breaking into his car. So everyday, he left the driver's door unlocked and put a small piece of clear tape on the door before he walks away from car. (so he can know whether anyone had opened the door)
And he never ever had anyone bothered to even open his door for a good 5 months until one morning, he found that the tape was tampered with a note left on his windshield inside the car that read "Dear car owner, FUCK you for leaving nothing. But thank you for your honesty, thief.