As a game master I have a story to tell, be that through running published modules or my own hair-brained story. The thing is though, much like video games have taught us through character developing side quests, the players' characters have their own story to tell.
I've run sandbox adventures where I just react to what the players do, or throw out hooks to see if they decide to follow. A very organic way of playing that just meandered about, but never really developed to any epic over-arching storyline.
I've run modules that are supposed to take characters on epic quests, but by their nature kind of railroad the players to take the next hook, or give up the evening for deviating from the proscribed material.
One thing I've come across recently though is the Plot Point campaign by Pinnacle game for their Deadlands: Reloaded series. I think it strikes a nice balance between the tow because it breaks up an over-arching story campaign into sections that can either be completed back to back or with other material thrown in between. There is a nice feel to the part of the campaign being wrapped up with either a fairly obvious hook that the players can activate if whenever they wish to continue, or has a new set up to string the next adventure in pretty much anytime. This allows for characters to pursue their own interests and agendas while still getting around to saving the world in a timely manner.
They system works kind of like this the main campaign adventure is the plot point, with each side mission being a short one session adventure in between.
1 Plot point mission
1-2 side missions
1 plot point
2-3 side missions
1 plot point
1-2 side missions
1 plot point
1 plot point
2-3 side missions
1 plot point finale
Side missions can consist of addressing background events in the world not directly related to "the quest"
They can focus on an individual character's background, goals or development, and you rotate though which character gets the spotlight each time.
The plot point pattern can be used as pattern for string of single adventures:
Even without a detailed campaign, just a matter of having a re-occurring villain make an appearance, without every conflict being about them.
Weird adventures can be inserted into a game to keep the creepy feel without having it become mundane, because they have non-weird happening in between
Side missions can consist of addressing background events in the world not directly related to "the quest"
They can focus on an individual character's background, goals or development, and you rotate though which character gets the spotlight each time.
The plot point pattern can be used as pattern for string of single adventures:
Even without a detailed campaign, just a matter of having a re-occurring villain make an appearance, without every conflict being about them.
Weird adventures can be inserted into a game to keep the creepy feel without having it become mundane, because they have non-weird happening in between