ThinkGeek’s Grow Your Own 1up Mushroom Kit might grant you “immortal life beyond dreams of man” if you eat it, but it also comes with the warning, “Do not put in face”. Such mixed messages from such a cool plant. The mushroom comes in a sewer-pipe pot, and only requires water, a food mixture, and a dark location to grow into a very realistic looking 1up mushroom. Just be careful, Bowser is on the loose again.
Edit: Sadly, this product is only available during April, and only to fools.