Now Leaving Bikini Bottom was a canceled special episode of SpongeBob SquarePants that was originally supposed to air in 2009. The special was seemingly canned after the series was renewed for an 8th season.
Not much is known about the contents of the special, but it was intended to serve as a finale to the series. Based on the title, it may have featured SpongeBob moving out of Bikini Bottom. The official site apparently described it as "their biggest adventure yet", and a "sponge-tastic adventure full of excitement and laughs".
No materials from the episode have ever been found asides from a listing on a now-defunct Nickelodeon site that promoted it as the series finale. All known info on the special comes from a forum post from April 3, 2009 that had a screenshot of the official website. It is unknown if this was ever produced.