Ever set up a scenario, hook and all, and actually encourage your players not to take it if they don't want to?
I did.
Last night my wife and I found ourselves free for the evening, so we called up our buddy Phil to see if he wanted to come over for pizza and gaming. He did, and I offered up a Traveller scenario. Phil's been itchy to try it out, and my wife is Trav-ready 95% of the time, so all systems were go. Phil rolled up an Army captain; she whipped up a Navy Lt. Commander in no time. I had the two of 'em muster out on Marden, a world in my Traveller universe (IMTU).
Marden, in a nutshell: Beach Resort Planet (B669669-7 Ri 212 Im if you're hardcore). It's a vacation spot run by a multi-corporate consortium. Hotels, casinos, open-air restaurants...swankitude.
There's an illegal drug making the rounds, and the corps want the suppliers gone. They offer the PCs a job: go to the planetoid belt, find the source of the drug, and neutralize 'em bastids. There's a mining outpost out there, owned by a separate corp; maybe they know something.
My players turned it down. They couldn't justify being part of the Corp's actions, being in the fuzzy gray area between what the Corp can do and what the Imperium should do.
Phil pointed out that if they didn't take the job, there'd be no scenario...and of course he was right. But for the first time in my GMing life, I decided to say, "Dude...I've got 76 Patrons, I've got BITS' 101 Plots. This is a game; you guys CAN say 'no', we can do something else."
Phil told the corp to shove it, and left; Amber said "I'm on vacation!" and left with him. It was 11:30pm, so we called it a night. No worries; there's plenty more to do on Miami World.
It was very different for me...not only to have players not take the hook, but also to allow them to slip. Especially interesting was that I decided, consciously, that they could do something else for which I had not prepared. My game felt like a world, not just a story. It was all up to them and their choices.
So help me, I felt like a brand-new GM.
[Oh, by the way – the illegal drug is called Huetlatonin-Beta, whatever that means. I made it up on the spot after my wife suggested calling the tabs "Hueys" as in "Lewis" as in "I Want A New Drug". RAWK!]