Tarot reading.
I do tarot reading on a little folding table on the street for extra cash. Tarot has nothing to do with the supernatural; it’s a form of applied psychology. The cards have been designed to be archetypal so that no matter which cards come up, they’ll always say something accurate about every person if they’re interpreted the right way. What I do is read the person, not the cards. I use eye movements, body language, eye motions, and word choices to play a game of “hotter or colder” with the meanings of the cards, reflecting back at the querent exactly what they’re telling me. It’s no different than psychoanalytic reflection, and indeed Carl Jung got much of his model from studying traditional mystic and shamanic practices like tarot card reading.
Tarot works because of a phenomenon called apophenia, which is the tendency for the human brain to find patterns even where there are none. In the absence of a pattern, the brain will actually project one from the subconscious. Tarot is therefore useless for telling the future, but it’s extremely effective and efficient at digging out what’s going on inside someone’s head on a subconscious level.
And the money’s not bad, either.