“ Adventurers are to capture an unknown monster for examination (for a sage or wizard) but they are themselves captured by the monsters, and researched.”
“ An old, misanthropic and paranoid man feels his time is coming. There are sons to leave his fortune to, but they are not worth it, not a dime do they deserve! And he doesn't really trust anyone else. And so he has made a decision: as a part of his last will, his henchmen are instructed to burn and destroy all his holdings, buildings as harvest. The lands shall be auctioned off, the proceeds used to pay the servants. Nothing shall stay behind. Nothing.
Depending on the status of the grumpy old man, this weird occurrence may be only a family drama, or it may end up bringing an entire region into chaos. Or the son(s) have found what should happen, and want to prevent it before their sick father dies.”
“ In a crowded marketplace, a man is standing on a soapbox, orating. Some of the crowd are cheering, some hissing, some standing around saying 'I can't hear a bl**dy word he's saying'. It's a hustings for an election. The PCs can either leave, or stay and listen. If they do the latter, then they can vote too, and they might get quite involved in the cheering. Depending on who wins they might get quite involved in the post-election brawl too...
There are numerous possibilities with this encounter: the PCs might end up talking to one of the nervous candidates before their speech, and offer encouragement and support. Of course this candidate may well turn out to be someone with outspokenly unorthodox views, and the crowd don't take kindly to s/his supporters. Or maybe the seemingly innocuous candidate turns out to be a complete racist, and the PCs wander off embarrassedly, pretending they weren't talking to this person five minutes ago.”