The Datacoin project started in 2013. Data is stored in the blockchain forever and can be retrieved using a transaction hash as an identifier.
Developers can store torrent files, certificates, HTML pages and other kinds of meta-information in the Datacoin blockchain. Windows users can use a GUI wallet and Linux users can compile datacoind or Datacoin-QT from source (see instructions). Mac users can download Datacoin-Qt.dmg. An online wallet is also available. More wallets are in development, and more features are being added, but the wallet’s current functionality is similar to other coins.
Primecoin-fork: same PoW method as Primecoin.
1 minute blocks
Total supply of 2,000,000,000 coins (approx 28 000 000 mined so far)
Exchange: BTCPOP Exchange. https://btcpop.co/Exchange/DTC