(From the nuclear power industry's false promise about electricity being so cheap as not being able to charge for it)

1. In a fantasy or western-european-Pagan setting, sorcerous things that use so little mana as to be insignificant and not get you persecuted if you use them. Dancing naked in the forest when no one's looking and no camera is rolling is witchcraft that's too cheap to meter.

2. In a broader sense, a deed in a gray area (of society) that's so small as to not even be noticed.
1. When Gandalf blew a ship made of smoke through a smoke ring it was a form of witchcraft that's too cheap to meter.
1. At 10:45 AM I took off all my clothes and went into the woods and did a thankful little jig when it didn't snow. I'm Christian, but it was witchcraft that's too cheap to meter.

2. Gina:"Are you downloading MP3 files again?"
Sean:"Yeah, don't worry, it's witchcraft that's too cheap to meter. You won't get caught."
2. In 1996 I took some toilet paper and stuffed it into the bathroom exhaust fan at my grandmother's house, she didn't mind because it was similar to witchcraft that was too cheap to meter.
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