A place where you could trade any asset you want with the network and get any asset you need/want/ask from the network...
Like selling in ebay and buying from amazon! But you sell to the network and buy form the network!
Sell any asset through a secure and decentralized orderbook - Your asset could be "inside trade" (trade inside the network) in order to find a combination where you could get what you ask. (eg. money or any other asset)
You could sell a service like repairing a car for food, you could sell pieces of art for bikes, houses for money, everything you need. But in fact you trade the service of repairing a car for piece of art, that was inside traded for money, that was inside traded for a 0.2 of a house and the food was traded for a 0.01 of the house and so one.
@bycz