Not completely sure about this, but probably SCRT and SEFI. SCRT is a working anonymous smartchain, and SEFI is its Uniswap with a great name, SecretSwap.

SCRT Nfts are very interesting. Imagine NFTs with hidden data that only the owner can read? One could sell stories, poems or quotes that only owners can read, and buyers can publicize those or keep them for themselves.

SCRT is ofc also useful for private transactions in general, good for criminals. Then again, Monero hasn't pumped well this year.