Since this is more of a discussion topic I thought it would go well here. Over the years I've read some lousy fanfiction. On the other hand, I've come across the rare gem that could almost be considered professional quality. Like a Star Trek TV tie-in that I might get at the library. (Some of those were pretty good) I'll read the story and think to myself, "This could have been the plot of an original novel. Just switch the main characters out and bam." Have you ever come across a fanfic like that? Or have you ever written an original story that started out as fanfiction?