I remember seeing a picture of this mushroom in a wonderful David Attenborough book. It was photoluminescent, and photographed by its own light. So in a fit of nostalgia (and possibly because I needed one for a magazine article) I created this model.
For those of you without adequate support, there is a *_kit.stl file that has the cap and stem separately. So if it doesn't print the cap properly, use that instead.