I've got one for you. I've asked my dev to do this, but he doesn't seem to think it's possible. Anyways, the basis of it falls on an ore type. This ore type is minable only in a certain mine. The mine itself would be inside a city that I'll end up creating. Now, the only way to get to this city is by a scroll (or talisman once those are added to the server). In order to use the scroll, you will have to have at least 125 mining and 100 magery. There will be a 2 hour timer on it, once the timer expires it will automatically teleport you back to the location you were at when you used the scroll. There is also a teleporter in the town that'll take you back to a specified location in feluccia so that you can leave at any time you want. Now, here comes the tricky part....
The towns ppl are all dead, however they don't know they're dead. They will walk around and do everything like normal, in fact you'll even be able to purchase items from the stores, if you were to have the correct currency. Which means that if you try to pay with gold, the vendor will say something about it not being real money or something like that. The townsfolk will talk about how they used to be a prosperous town and how the ore in their mine used to be highly sought after until the cave-in which enclosed their society. Since then they have sworn to protect their ore from outsiders.
Now, IF a person is capable of mining this ore, they then have to go through town to the teleporter, since recall, gate, and mark will not work in this area, or wait for the timer to expire. However, if they walk through town and are spotted by an npc, that npc will start attacking them if they have the ore in their pack (this would include inside containers within their pack). The npc will also call for help and pretty much the entire town will come out to stop the intruder from escaping with the ore. Also, there will be townsfolk in the mine, so they will immediatly approach the player as soon as it's put into their pack.
The scroll will be able to be used as many times as possible as long as the timer is still active. The timer will remain active even if the player logs out. once the timer has expired, the scroll will be deleted.
Also, I've been trying to figure out how to make a few containers come up while harvesting. For example, while mining you might come across an old chest or maybe even a corpse that'll have ancient loot in it, perhaps even an ancient currency. And while lumberjcaking, you might knock down a bird's nest that is filled with goodies.