What is the most leisurely psychological trick you can play on someone?

1.Want to give someone a sense of power without giving Power: 

Whenever talking with someone & you feel they're not paying attention to you, stop and ask for their permission to continue the conversation. You'll get their full attention because now listening to you is their own choice (they feel important & influential).

2.Want someone to feel uncomfortable:

Someone staring at you in the subway happens all too often – look at their shoes. Please don't give up; keep gazing; it'll drive them crazy. Most people will feel like they're under scrutiny.

3.Want someone to like YOU:

Let's say you started a new school or job; if you want someone to like you, at your office or class, ask them to explain something to you. It doesn't matter if you know the answer.

4.Want to correct someone without correcting:

You can draw someone's attention to their mistake without accusing them of merely changing your sentence. Instead of saying, "You didn't close a window before you left," you can say, "The window was left open all night."