You can wish anything, and the wish will be fulfilled; but your worst enemy will get twice as that. What can you think of besides classical “put out one of my eyes”?
The story was first published in Playboy magazine in March...
It's well established now that the way you put a question often determines not only the answer you'll get, but the type of answer possible. So ... a mechanical answerer, geared to produce the ultimate revelations in reference to anything you want...