You can read the dregs of black, instant coffee the way you can read tea leaves in a cup.

1) Place your normal amount of coffee powder in your cup.
2) Pour a little hot water into the cup. Do not stir. Instead, gently make the liquid swill at the bottom of the cup.
3) Add as much hot water as you want.
4) After consuming the coffee, you will note an image at the bottom of the cup. Interpret properly.

You will be surprised at the myriad of images the coffee cups will give you.