I used to freak people out with minesweeper.
There was a hack that allowed you to know what was under every single square. When it was turned on, as you hovered over a square, if there was a mine there, a single pixel at the corner of your computer screen would turn white.
I went into an egghead computer store once and drove the staff crazy. I did it in “difficult” mode. I’d clear out the entire board and win without flagging any squares. I finally told them what I did.
I thought that game was called “mindsweeper”.