Here is a list of altcoins based on Ethereum. Their code is a fork of go-ethereum.

Each of them can be used as a digital assets platform, and can run smart-contracts.

They are ordered by rank on Coinmarketcap.


Ethereum Classic
The original version of Ethereum, focusing on censorship-resistance, immutability and decentralization.
https://coinmarketcap.com/currencies/ethereum-classic/
https://www.ethereumclassic.org/
https://bitcointalk.org/index.php?topic=1559630 and https://bitcointalk.org/index.php?topic=5134923
https://www.reddit.com/r/EthereumClassic/
https://github.com/ethereumclassic/


Tomochain
Tomochain introduces a network of 150 Masternodes with a Proof of Stake Voting consensus. This network of masternodes enables better scalability, near-zero fees, and near instant transactions confirmation.
https://coinmarketcap.com/currencies/tomochain/
https://tomochain.com/
https://bitcointalk.org/index.php?topic=2021785
https://www.reddit.com/r/Tomochain/
https://github.com/tomochain/


Etherzero
Etherzero introduces a network of Masternodes with a Proof of Stake consensus. There is no voting contrary to Tomochain. This network of masternodes enables better scalability, near-zero fees, and near instant transactions confirmation.
https://coinmarketcap.com/currencies/ether-zero/
https://etherzero.org/
https://bitcointalk.org/index.php?topic=2607526
https://medium.com/@etherzero
https://www.reddit.com/r/Etherzero/
https://github.com/etherzero-org/


Ubiq
Ubiq is built upon a modified version of the Ethereum codebase, puting stability at its core.
https://coinmarketcap.com/currencies/ubiq/
https://ubiqsmart.com/
https://bitcointalk.org/index.php?topic=1763606
https://www.reddit.com/r/ubiq/
https://github.com/ubiq/


Callisto Network
Callisto Network introduces the possibility for holders to gain passive income by staking coins.
https://coinmarketcap.com/currencies/callisto-network/
https://callisto.network/
https://bitcointalk.org/index.php?topic=3380156
https://www.reddit.com/r/CallistoCrypto/
https://github.com/EthereumCommonwealth/


Pirl
Pirl introduces a 3 layer network of Masternodes with a Proof of Stake consensus : premium masternodes, storage masternodes and content masternodes.
https://coinmarketcap.com/currencies/pirl/
https://pirl.io/
https://bitcointalk.org/index.php?topic=2120193
https://www.reddit.com/r/pirl/
https://github.com/pirl/


Ethersocial
Ethersocial focuses on optimized development of the reward system for online forums and games.
https://coinmarketcap.com/currencies/ethersocial/
https://ethersocial.network/
https://bitcointalk.org/index.php?topic=3126487
https://www.reddit.com/r/ethersocial/
https://github.com/ethersocial/


Expanse
Expanse was the first stable fork of Ethereum. It focuses on identity, governance, charity, commerce, and equity.
https://coinmarketcap.com/currencies/expanse/
https://www.expanse.tech/
https://bitcointalk.org/index.php?topic=1173722
https://www.reddit.com/r/ExpanseOfficial/
https://github.com/expanse-org/


Ethergem
Ethergem introduces a network of Masternodes called Quarry nodes, based around discord.js and web3.js.
https://coinmarketcap.com/currencies/ethergem/
https://egem.io/
https://bitcointalk.org/index.php?topic=3167940
https://www.reddit.com/r/egem/
https://gitlab.com/ethergem/


Ether-1
Ether-1 integrates a three tier masternode system to secure the network : Service Nodes, Masternodes, and Gateway Nodes.
https://coinmarketcap.com/currencies/ether-1/
https://ether1.org/
https://bitcointalk.org/index.php?topic=3725742
https://www.reddit.com/r/Ether1/
https://github.com/Ether1Project/