This idea just popped into my head while seeing all the people asking for favors and other things for quests.
An easy way to get others to do things for you. You could use it as an auction house GUI. Once they type in a command it brings up a GUI that allows you to either:
A. Put up a quest, setting a reward and what you want.
B. Browse quests, and find work to do for money, allowing market chat to have less “Buying workers” and “Looking for work” while giving opportunities for newer players.
Upon finishing the quest you can put the items in a GUI and the player who gave out the quest can see the stuff inside (If its a build or demolish quest just put in something upon seeing the correct items inside they can click a “quest done” button which gives the rewards to the questee and the blocks or whatever to the person who gave out the quest.
If a way to scam is found it should be a warning or a bannable offense.