Sit in the middle of a room in everybody's way and don't move and don't look at anyone.
Go buy a watermelon and a few hundred rubber bands, attach all of them onto the middle of the watermelon until it explodes.
Dance to your favorite song in the middle of the street and once a car comes point at them and run.
Pretend to fall dead in the middle of the library, and when someone walks up to you grab their leg and tell "BRAINS"!
Text a friend in the middle of the night "coming over now be there in 5 minutes" then wait for a response.
Make a squirrel out of duct tape, put it in the middle of the road and see if people drive around it.
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