Crash Nebula is the twenty-first episode of Season 5 of Fairly OddParents. It aired on July 2, 2004, but is considered part of Season 5 in production and this episode was technically a backdoor pilot of this show.
History of Production
Butch Hartman had attempted to create Crash Nebula as a spin-off animated series. After a long while of speculation, Butch Hartman confirmed on January 24, 2006 that the whole project was called off and that the series was not going to be made. He does, though, intend to "keep trying", and the concept may come back someday.
The concept was also written as a movie script and pitched to Paramount Pictures as a feature film. It would have been entitled Crash Nebula: The Movie. However, it was rejected, as there were too many similarities to Sky High, a movie already being put out by Walt Disney Pictures. Crash Nebula is very similar to and possibly inspired by an earlier cartoon, Galaxy High.
Due to the proliferation (and eventually cancellation) of Danny Phantom, as well as the debut of T.U.F.F. Puppy and Bunsen is a Beast, this idea has likely been scrapped by Billionfold Studios.