Emercoin (EMC) is the mineable coin based on the Emercoin’s own blockchain. You can convert these coins to other cryptos and back on a few exchanges. Emercoin was launched as early as in 2013 as the Peercoin’s fork.
SpankChain (SPANK) is an ERC-20 token offerd by the SpankChain network. The cryptocurrency pairs including SPANK are available on the number of exchanges. One can also buy the coin in exchange for USD currency, using one of the exchange platforms.