Many of you in the AltCoinArmy have been asking us to look into 0x, and we finally did.
This project looks like a promising way to allow application developers to build their programs on the Ethereum platform without having to rely on the normal processors and costs associated with trading on the Ethereum blockchain.
Additionally, like the Lightning protocol, this will (and does) make Ethereum more scalable as it goes mainstream. Transactions of exchanges can take place off the blockchain through 0x liquidity pools.