A fork of LISK and went public around October of 2016, ARK is currently ranked ~25th in market cap and has almost 100mil coins in circulation. It is around 40,000 satoshi per a coin.
This is one of the coins I have followed ever since I started learning about cryptos. Ark is a delgate proof of stake coin and were coin holders delegate their shares of Ark to an elected delegate to earn more. The nominated delegates would then have to maintain the blockchain and operation of the Ark network. The delegates receive a service fee that is shared with the people whom voted for them. Each delegate will have their own methods of sharing their earnings with their supporters.
What makes the coin useful is that Ark has a platform that allows integration of different blockchains and allow them to seamlessly work together. Ark named this as smart bridge. A tall order to ask to do but if it is succeeds in what it was set out to accomplish the value of this coin is limitless. Just think exchanging different coins without a third party exchange or applying the functions of one's blockchain with another to make it solve multiple problems at once.