This is the not the nicest example.

My friend and I use to do this con, where we would go somewhere where there were people hanging about. Coffee shop, bar, restaurant, whatever. My friend would wander around chatting up people and would find a group to start start talking to. I would go sit alone and pull out a deck of cards and do some flourishes, and my friend would help other people notice what I was doing. Eventually, I'd have a crowd and I would start doing magic tricks.

Once we had enough people engaged and did enough magic tricks, I would "explain" how I could put two cards together in a deck, one on top of the other, that no matter how many times I cut the deck the two cards would always end up together. I would do this by taking two black aces, cut the deck in half, place one ace on top of one half and then place the other ace on top of the first ace and then put the second half on top of both aces, then I would cut the deck multiple times, then have someone else cut the deck at the end. I would flip the cards over, one at a time from the bottom, face up until I came to the first ace. I would explain to the crowd that no matter how many times I cut the deck the two black aces would always be together. After the first ace showed up I would say something like, "I bet the next card will be the other black ace." then I'd say, "of course you wouldn't bet, because no matter how many times you cut the deck the two aces will be together" and as I said that I'd flip the next bottom card over to reveal the other black ace".

It's completely stupid. There's no trick. It's common sense.

Then the con would start. I would say, "let me show that it always works", and I would start to repeat the process. I would take the two black aces out of the deck and hold them up. I'd cut the deck in half into two piles on the table and say that if I put the two aces together, no matter how many times I cut the deck they will always be together. I'd put the first black ace on top of one pile, but then I would get distracted, say by dropping the other ace on the ground. While I was bending down to pick up the card off the ground, my friend would take a few cards from the other pile and place them on top of the pile that had the first black ace on top of it. I would stand back up and go back to talking, seemingly unaware of what happened, and go back to "explaining". I would take the other black ace and place it on top of the pile that had the first black ace on it. The pile that now had an ace with a few cards on top of it, and then the other ace on top of those cards. I would put the other pile on top of those cards and cut the deck a few times. Watching the reactions of the people who thought they were all in on this inside joke that I wasn't aware of was always priceless. Only one person every said, "hey, he put cards on top of the other ace", and he was mentally disabled. Everyone thought they were in on this big joke and it was going to be hilarious. I would go through my spiel about how the two black aces would always be together, and start turning over the cards one at a time from the bottom, face up. I'd come to first ace, and say the same thing I said before. "I bet the next card will be the other black ace." then I'd say, "of course you wouldn't bet, because no matter how many times you cut the deck the two aces will always be together." At this point my friend would interrupt me and say, "I bet you." I would laugh and tell him, "No, that's silly. I'm telling you the two aces are always together." He'd pull out twenty dollars and say, "I'll bet you twenty dollars." I would laugh and tell him that it's ridiculous, I can't take his money. He'd insist. I would finally reluctantly agree, pull out a wad of cash and put twenty dollars down on the table with his and say, "okay, but it's your loss." THEN I would say, "Anyone else?"

Every fucking time people would start pulling out money and want to "bet" that the next card wasn't the other black ace, because they saw my friend put the other cards on top of the first ace. What started out as an inside joke between them and pulling one over on the magician, now turned into what they thought was free money. We'd put all the money down on the table and I'd flip over the next card, and it was the other black ace. Then I'd explain all jokingly, "I told you the other card would be the other black ace." I'd pick up the money, put it in my pocket, and make my gracious exit. Meanwhile, my friend would be distracting the group by acting just as surprised by what just happened as they were. Eventually we'd meet up outside afterwards and split the profits. Never made less than $50. Worked every time. It was more about the skill of doing it, than the money itself. After a while it wasn't interesting anymore, and we just stopped doing it.

This taught me that people will do bad things if they don't think there's consequences and they think they can get away with it, people are human, which isn't necessarily bad, and if you put them in the right scenario, they will respond predictably. That's why, if you put a thief alone in a room with a wallet, you know the outcome beforehand. Which means you can get people to do whatever you want, within their personality range, of their own free will by constructing the right scenario.

On the flip side, you can create a beautiful moment with a complete stranger with a simple "hello". Which Amanda Palmer explains better than I can.