Vehicle Theft Prevention
30 years ago a car could be stolen using nothing more than a metal coat hanger. Then we got electronic remote locking which could be overcome if thieves captured the signal as the car owner uses their remote. Later developments saw the signals encrypted and randomized which helped prevent this sort of theft.
Now many new cars have keyless entry and push-button start which is flawed because it can assist thieves to steal cars with little effort. Thieves simply boost the weak signal of the fob kept in your home and transmit it to a second thief standing next to your car. The car thinks that's you with your fob and unlocks its doors to the thief who drives it away and sells it whole or for parts.
This sort of theft can be prevented with a very cheap solution. See below.