Head Worker

It is said that if you can't unlock your car with your bipper because you're too far from it, if you hold the bipper to your head it will work, as your skull or the bag of water inside it acts as a resonator and amplifier.

I listened to a science programme a couple of weeks ago that debunked the claim, maintaining it was probably due to you holding the bipper higher when putting it to your head and getting a more direct line-of-sight.

However, I tried it the other day when approaching the car in the dark with no direct line of sight and a wall between me and the car. I could tell whether the car unlocked or not from a reflection on another wall.

I kept locking and unlocking the car while going further away from it, holding the bipper at head height, but well away from my head. When the bipper no longer worked, I put it against my temple and, hey presto, the car unlocked. 

I repeated the experiment while taking a step further away from the car each time, until not even the head shot worked. Holding it to my head definitely worked for me. Perhaps only my head works, because it's empty.