This video is presented for its technical merit only. Do NOT attempt to do this. Modern meters will flag tampering like this, and the actual act caries a high risk of electrocution or burns.
In the dark past, devices called “retarders” were sold on the black market from shady vendors in pubs, from car boots and from under dodgy market stalls. These devices were indiscriminately sold to non-technical people by equally non technical people to make their meters run backwards. The idea was that you hooked this thing up to your meter by jamming wires up its terminals, and it could be used to wind your meter backwards to reduce your electricity bill.
The downside (and it’s quite a big one) is that the units were not really suited for non technical people and if you either put the wires in the wrong place or connected them in the wrong sequence, you would either end up getting a shock or severely burned, with the possibility of taking out the supply authorities fuse, or even the whole street.
These things were also quite severe in the current they passed through the meter, and would often leave scorch marks on the terminals, burn the insides, or in the case of misconnection, completely destroy the meter. All things the supply company would look for when you opened the door to them while whimpering quietly with the charred remnants of your skin falling off your hands.
Latterly devices to detect this activity were added to meters in the form of non-resettable flags that would move out if the meter ran in the wrong direction, or in the case of digital meters a tamper indicator.