“ The secret for immortality has been discovered by an eccentric wizard/mad scientist. Its found you need to reapply once a month. As people stop dying, and the birth rate increases exponentially, people are forced into homelessness, because of the need for food reamins the same, and food is not being produced fast enough to feed the undying population. The PCs have to find the creator and kill him, and destroy production, to save the world from undying, unending torture from hungryness.”
“ The Yugzhee, or 'hedgehog-people', guard a great, secret treasure inside their giant burrowed lair. The mysterious Wall of Keys, a 12'x10', foot-thick, cold-iron, 'wall', upon which, on iron hooks, hang 100 ornate iron keys of all shapes and sizes. Each key opens some heretofore un-openable barrier, door, or gate, in the particular game world of choice.
The PCs have come upon a great boon, except for the fact that the keys cease to function properly if separated from the iron wall for more than a few minutes. Higher level characters will be able to figure out how to take the wall 'with them' via magic. Lower level characters will have to get creative.”