Loom Network (LOOM) token is currently based on cryptocurrency Ethereum protocol. It is represented on a fair number of exchanges. Loom Network plans to be the connecting hub for various blockchains. It provides dapp developers with the tools to integrate assets from major chains, such as BTC, ETH, Binance and TRON (with EOS and Cosmos coming soon). You can also earn LOOM tokens for participating in the network as the reward or bounty.
The SONM (SNM) project was released in 2017. Cryptocurrency pairs with the SNM token are represented on the number of exchanges. SONM is currently based on cryptocurrency Ethereum protocol.
Tezos is a smart contract platform with its own blockchain and a native token (Tezos, XTZ). The governance is performed via Proof-of-Stake algorithm. It means that stakeholders (those who own at least 10,000 XTZ) vote for changes in the protocol. These validators ("bakers") get rewards for the performance of validation. The rewards are generated via inflation. Those who delegate their XTZ to bakers can earn, too.
Tezos has a built-in "self-amendment" mechanism which makes it possible to shape the network without having to make forks. It keeps the community united and makes development process easier.