GameCredits (GAME) is the mineable coin of the GameCredits project. The coin is listed on a few exchanges. You can trade GAME against USD on the BitBay exchange.
Zcash (ZEC) is a cryptocurrency with strong cryptography that is supposed to provide high security and privacy. At some point, Zcash was endorsed by Edward Snowden and Roger Ver. Zcash is a Bitcoin fork and it exists since 2016. The mechanism providing privacy is called zero-knowledge proofs (or zk-SNARKS).
Gnosis (GNO), the native token of the Gnosis platform, is based on the Ethereum blockchain. The token is paired with other cryptos on several exchanges.