I've been reading comic books for most of my life. Some of them are very episodic, but others build complex storylines across multiple issues, treating each issue as a chapter in the story.
Among the various things that interest me about comic book mythology is the way in which relatively minor powers get explored and applied. This is particularly true among the Marvel Universe mutants, but it shows up in plenty of other places. Just to choose an example from a completely different genre, consider Emma Bull's Finder - a novel set in Bordertown, where the Faerie Realms have returned to touch Earth again. The main character has a power which sets him apart from other people, which makes him into both a freak and a hero. His power...
...is the ability to find things. He's a locator. Tell him what you're looking for, and he can lead you to it.
It's not especially potent, and it's certainly not useful in combat. But it's an extremely useful ability in everyday life. And it gets him into trouble as much as it helps him out of it, maybe more.
So tell me: what are your favorite underappreciated powers? What abilities offer the most potential for clever use? What superpower might make someone famous, outside of superhero slug-fests? If you could have one stupid little ability, what would it be?