Ethereum   - Promises to be the first p2p smart contracts provider without the middleman. Not quite there yet, but the team and support are strong.
Ripple   - p2p payments for the banks. Works fine.
MaidSafeCoin - Decentralized internet. I dont think thy are quite there yet, but the idea is interesting.
Dash            - Trying to be the best bitcoin. Allready has solved 0-conf problem with its instant-x tech, robust optional anonymity, rewarded full nodes, core integrated governance and budgeting system etc. All those previously mentioned things allready in working condition, not final but still working. Many great ideas and promises for the future release.
Factom   - First decentralised p2p fully transparent accounting system for businesses etc. i dont think they are quite there yet but again strong team and support.
Dogecoin   - First successful meme currency. Works fine, but lack of innovation and depends on litecoin network.
BitShares   - Decentralized Exchange. Many good ideas and a lot allready working.