Here are some cryptocurrency rankings for proof-of-work (PoW) consensus mechanisms (in no particular order):

(PoW is the essence of the cryptocurrency ecosystem)

- **Bitcoin $BTC**: As the original and most well-known cryptocurrency, Bitcoin popularized the PoW mechanism through its mining process.

- **Bitcoin Cash $BCH**: A fork of Bitcoin designed to increase transaction processing speed through larger block sizes, still using PoW.

- **Litecoin $LTC**: Often called the “silver” of Bitcoin, Litecoin uses a different mining algorithm but is still based on PoW.

- **Zcash $ZEC**: Known for its privacy features, Zcash allows private, shielded transactions by default and employs PoW.

- **Monero $XMR**: Focused on privacy, Monero uses the PoW mechanism of the CryptoNight algorithm to ensure that transactions are untraceable and unlinkable.

- **Ravencoin $RVN**: Designed for asset creation and transfer, Ravencoin uses the KAWPOW algorithm and is ASIC resistant.

- **DigiByte $DGB**: Its PoW mechanism combines multiple algorithms, including SHA256 and Scrypt, to enhance security and reduce centralization risks.

- **Grin $GRIN**: Known for its privacy-preserving Mimblewimble protocol, using the Cuckatoo32 algorithm for PoW.

- **Beam $BEAM**: Another cryptocurrency based on the Mimblewimble protocol, using the Equihash algorithm to implement PoW.

- **$POWR**: Although primarily known as a blockchain for renewable energy trading, it is possible that a PoW mechanism may be used, although this is not explicitly confirmed.

- **$SMH**: Mentioned as a PoW token with smart contract functionality.

- **$QUBIC**: Attracted attention for combining PoW with artificial intelligence, indicating that it is a PoW-based cryptocurrency.