Unobtanium is a Proof-of-Work (PoW) cryptocurrency that uses the SHA-256 hashing algorithm. It was designed to serve as a commodity and store of wealth that would be less vulnerable to price fluctuations. The coin's supply is limited to counter inflation, and UNO coins were distributed in a manner that would discourage centralization. UNO can be merge-mined with Bitcoin.

Sharechain is developing a Proof-of-Work cryptocurrency platform. Their network is currently fueled by the Ethereum-based SSS token. Their marketing materials are unclear and do not offer any information about its advantages.

Litecoin is a crytptocurrency that was created to serve as the “silver” to bitcoin’s "gold." It is based on the core Bitcoin protocol, but was designed with several key features that provide it with advantages over Bitcoin.
Litecoin has significantly reduced transaction times by limiting the target block processing time to 2.5 minutes. It also has a total coin supply that is 4 times larger, and utilizes a different hashing algorithm called Scrypt, that requires a smaller workload and less computation power than Bitcoin's SHA-256 algorithm. This enables much faster transactions at a much lower cost to users. These features make Litecoin easier to use and to mine. Since its creation, Litecoin has gained a large market cap and widespread adoption among cryptocurrency users in need of a coin for everyday transactions.