Check out this Miracle Fruit.

Apparently, eating it makes sour things taste sweet.

A chemical in the flesh of the fruit coasts the taste buds and alters their shape, making the taste buds that stimulate the sensation of sweetness more receptive to acidic stuff (sour tastes). So, while you are stimulating the normally sweet tastebud with a sour substance, your brain coasts off of absurd sweet flavour.

I can only imagine how absurd it would be to eat a spoonful of horseradish sauce and have it taste like ice cream or something…but apparently people have done that. There are descriptions of all sorts of crazy food adventures.