Mine are: Ethereum, Litecoin, Ripple, OmiseGo, Lisk, Golem, Augur, Lunyr, District0x, Bancor, 0x, Factom, Civic, Aragon, AdEx, and DigixDao.
We have similarity with Ethereum, Litecoin, Ripple and Omisego. And here are some of my favorite alt coins in addition, Monero, NEO, IOTA, BCH.
I still have some other alt coins that will be added to my portfolio and these are Zcash, DASH, DGB and NEM.
Ethereum is the most popular if we talk about the alt coins. Ethereum has the potential to be the next big thing after the bitcoins and it is also performing accordingly. I think people should back the ETH and start investing into it for longer period which may change the fortune of this coin.
Yes it is the most popular and it's smart contract made it very popular.