Nxt Decentralized Exchange
How are crypto coins currently traded?
Well you have to sign up for an account on a centralized platform such as Cryptsy/BTC-E/Bter/etc, transfer your BTC to them, and pay them a varying percentage fee for transactions. This features a large concern about the risk of unregulated centralized exchanges stealing funds, which actually occurred recently when the Sheep Marketplace absconded with 96,000 BTC, resulting in the largest theft in history.
Nxt is developing a peer-peer exchange into the protocol to allow for decentralized trading which will eliminate this trust point and to reduce trading fees to regular network transaction fees.