If you grew up in the 60's, then you're probably familiar with Atom Ant. His popularity waned in the 70's and remains relatively obscure today. Atom Ant was a super hero cartoon character who used his powers to fight crime. His diminutive size gave crooks a false sense of security until they found themselves hoisted in the air. In the clip below, Atom helps out an actor who plays his television hero, Super Guy at a personal appearance.
Though there's never been a dedicated DVD release of this Hanna-Barbera show, it can be found on several compilations. There's been talk of a live action version for film. Segments can be found on YouTube like the one above, uploaded by duckstalgia.
Obscurity factor: 2 (has something of a cult following, included in DVD compilations, available onYouTube)