The imaginary line marking the difference between AppliedPhlebotinum which is a cool and interesting adjunct to the story being told, and AppliedPhlebotinum which ''is'' the story being told. Story quality plummets dramatically the further past the Roddenberry Line you get.

What side of the Roddenberry Line you're on can often be determined by the amount of {{Technobabble}} you have to wade through before you can find a real plot point or a believable character.

The term was coined by Ben "Gryphon" Hutchins of EyrieProductionsUnlimited, and named (of course) for the late GeneRoddenberry, creator of ''Franchise/StarTrek'', whose enthusiasm for the gimcrackery of TheFuture occasionally overwhelmed his training as a writer.

In the science fiction genre, the derogatory term for stories that go ''well past'' the Roddenberry Line is "Tour of Wonder", where the protagonist exists mainly for the purposes of having someone for the future/alien people to {{Technobabble}} at. They can't just do it to each other, because that would be like one of your friends suddenly saying "AsYouKnow, Bob, this miraculous device that transforms the sound of my voice into electrical impulses that can be sent great distances before being transformed back into sound, allowing me to speak to people ''up to dozens of miles away'' as if they were right here, is called a ''telephone''."
* ''Anime/LupinIIIDeadOrAlive'' does its best to straddle the line of this trope. {{Nanomachines}} are first introduced as a BoobyTrap protecting the national treasury of the Zufu nation. Explanation occurs at a mostly gradual pace, as the gang learns more and more about how to bypass the Nanomachines to get to the treasure.