I do quite like unaware scenarios, especially involving characters who are friends. Futile attempts to get the other's attention, but they're also your only way to salvation.

Preferred size is a difficult one... lately it's been far beyond galactic, like, treating multi-/omniverses/realities like dust. For teasing though, I do enjoy having micros be like pieces of lint. Barely able to feel them, perfect for unaware scenarios.