Online Item Trading

It might be cool if players could put up items for trade on a place called the Global Market. You could choose an item to give away (it would become locked in your inventory so you couldn't salvage it unless you canceled the trade) and then choose 1-3 possible items you would accept, or you could emeralds instead. It would be a way to help players get items they want. Now, it may be way too good for lower level players to get crazy unique's, so I think that if you made all items traded, scale to the obtainers power level, that would be good. Also, only allow players to make and accept trades with players in their level range. So players at level 3, could only trade with players at a max level of 10, or something similar.