Craft idea: Alien

So there might be some legal issues involved in this but anything you can make hearkens back to the chest bursting scene in the movie Alien is bound to bring you attention and some money. See this: http://www.boingboing.net/2011/06/28/alien-wedding-cake.html

On a more serious note though, if you take public domain works and transform them into something edible, cute, impactful or whatever you can find a market for them. Think of a metal work rendition of the Last Supper or a wood block carving of the cave paintings in Lascaux, France. Or even a diorama of the Battle of Isandlwana.

Your obsessions can be profitable if you can communicate them in a new way so think about what you know well and then think about various forms of media/art; you never know. If Mark Kurlansky can make money on a book about Salt or Cod then you know there is a market for you somewhere.

Mark Kurlansky's books:

Salt: A World History & Cod: A Biography of the Fish that Changed the World