Free tools
Some people kept stealing small parts from this person’s father’s old truck, which was parked in the back of their property (cap, rotor, points, etc). They connected it to a power supply for an electric fence. They returned one evening after hearing a lot of yelling and swearing, and the guy left them some free tools.
Birdseed
This individual discovered their flatmate lying to mutual friends about them. She had made plans to leave the following month. Meanwhile, her friend left town for a week, leaving her car parked in its usual spot in the parking lot. So, she tossed birdseed on it every morning and evening so that the birds wouldn’t leave her car alone when she returned home.