Genesis-mining has been a trusted resource for many involved in cryptocurrency including youtubers like Treyvon James and Crypto Nick. It has offered mining for bitcoin, litecoin, dash, monero, zcash, and my favorite, ethereum. Up until a day ago, the only coins that you could start mining were ethereum and monero as contracts for all other coins were sold out. A day ago, they reintroduced bitcoin mining in a new open-ended contract. More info on the newly available bitcoin mining contracts at genesis-mining.com
As mentioned above, I personally feel that ethereum is the most lucrative to mine. However, the value is in the eye of the beholder. Nobody truly knows 100% which mining contract will be the most profitable in the long run. If you think mining could be right for you, head to https://www.genesis-mining.com for more info. If you decide to pay for some mining, use this code at checkout to get 3% off your purchase price: 9iEgeW