Inspired by the second weekly challenge in /r/rpg (Yes, I know that I posted one from the same inspiration yesterday. I got in on it late.):
The party arrives in a small town (For my game The Hamlet of Hysionat) in the center of a massive storm system. The party has obviously wandered astray somehow, but they shouldn't realize how badly yet. The town has a completely random population, composed of young, old, and in between. The exception is that no-one under the age of 13 lives there. They will gradually become more and more uneasy as half remembered faces assail them from every side. What it is, is the City of Suicides. All those who kill themselves non-altruistically go here after dying. If the party stays too long, they will begin to see the wraiths of those who killed themselves in their individual pasts. This will eventually lead to pleas for them to stay and "help".If they agree they will be found dead the next morning unless they pass a skill check.