RangerWickett
Legend

It's something that only happens when you let a game develop long enough. The game stops being a story delivered by the DM, and starts being one crafted by the entire group. Players take time to get into their characters and get a feel for the world, and the importance of what's what takes a while to sink in. But once everyone knows the basics, the DM can stop forcefeeding adventures, and instead let the group decide what they want to do.
For me, this time, it was after about six months and nineteen sessions. The group had mostly been helping a larger organization defend against its enemies, but last night, they started planning what to do on their own. Of course, this wasn't a conscious decision on their part; it came from them screwing up.
Y'see, a couple of sessions back, they defeated a powerful psionic monk (with the aid of a dagger that suppressed psionic powers). An ally of theirs cut his heart out and revealed a gemstone, then gave it to the party for safekeeping, suggesting they keep it and the dagger near each other at all times. One time the group ended up not keeping the dagger close enough, and the spirit of the psion that is trapped in the gem manifested itself and wrought havoc for about 3 rounds before they realized what was going on and put it back near the dagger.
So they know the gem holds the spirit of the psion they killed. They also have a magic item that is fueled by eating souls: if you use this bone club to kill someone, it sucks their soul, ignites to burn like a torch, and lets anyone who sees the flame of the torch teleport. Well, the group is in desperate need of teleporting to help save the day, so even though they wouldn't normally destroy someone's soul, they figure they can spare the psion's. For reasons not yet clear to the group, though, when they shatter the gem with the torch, instead of sucking out the psion's soul, the soul escapes and flies away toward its old haunts.
The group follows, and when they catch up, they see the psion's body is regrowing from a few stains of blood on the ground. They begin hacking at it, but it heals faster than they can wound it (and they're wounding it quite severely). They only manage to defeat the psion monk through serious pain to themselves, but manage to kill him and continually leech life energy from him so he can't heal. But they realize that they can't keep constant vigilance over this guy to make sure he doesn't revive and kill them all, so they do a lot of magical information gathering, and learn, surprise surprise, the monk is immortal.
He's one of four immortal people, actually (they already knew about two others). He'll heal from anything, and the only thing that kept him from being a major threat before was that his soul was trapped in a gem; he had no real body, and could only psychically project one. Now they've let him free, and even the anti-psionic dagger doesn't stop his immortality. They have to find a way to trap him permanently, or maybe just de-immortalize him. And the group starts making plans.
Bear in mind, this caught me completely off guard. I didn't think they'd try to break the gem that was holding the soul of a nasty evil guy they had a hard time killing the first time around, though I did know what would happen if he got free. So while they're fighting him, I'm thinking of how I'll be able to guide the party to find a solution, but then they go and surprise me by starting to look for their own solutions.
Suddenly, they start making connections between all the hints I'd dropped. So now, on the one hand, I'm going to have to plan fourteen dozen different ideas since they have huge flexibility, but on the other hand, it's their story now. They're still a little uncomfortable with being in charge, but it should be fun to see what they do.