When I was a student living in a house of 10 guys one of our housemates dads came over with a carrier bag with something heavy in it. He asked if we wanted to pay more or less for our leccy bill. Being skint students we of course opted for the latter.
He went down to the meter and attached a shoebox-sized box to it with a couple of wires and the meter wheel stopped 😯
It used to get mighty hot, that box.he came over once a month to disconnect it for a few days so we would register a small bill.
I think back on it now and wonder how we were never caught/arrested/burned in our sleep.