Everyone can think of a favorite song or two (or three) which can easily be translated into a fantasy rpg concept, be it an item, plot, location, or what have you. Just take the lyrics of your favorite real-life ditty, and go from there!
This is a scroll for every rumor or tale you might here from a friend or in a bar.
The characters are unwittingly embroiled in a rebel organisation, and must lead the Black Shield fighters to victory against the evil Halar, seeking out new hideouts, rescuing people from towns and generally doing what Robin Hood would have done in their situation.
The local band of 'nasties' (goblins / orcs / whatever) lives in relative peace with the local population.
Along come the PCs and go through their usual heroic monster bashing routine, wiping out the nasties and pinching all their stuff, then continue on their way.
Problem is, they don't kill ALL he nasties. The survivors want revenge and, after spending a few months recovering, start to take it in their own inimitable style (which is not unlike that of the PCs come to think of it).
Next time the PCs are in the area they find themselves VERY unpopular with the townsfolk.