`Flat 211a & 211b shared expenses: $614` Skimming over your electricity bill, you notice that it's almost $500 more than last month, even though you didn’t change your habits in any way. You remember seeing the girl next door move in last month. She didn’t bring much furniture, it was mostly boxes of wires and electronic equipment. Since the two flats are on the same energy meter, there must be something going on. Just then, the ceiling lights briefly flicker, as if responding to a power surg...